Pokemon: Let's Go, Pikachu!

Free original Pokemon starters
To get the original Pokemon starters for free, complete the indicated tasks:
Bulbasaur (grass type): Once you have caught 30 Pokemon, talk with a woman in her home in Cerulean City to get a Level 12 Bulbasaur.
Charmander (fire type): Once you have caught 50 Pokemon, talk with a man on Route 24 above Nugget Bridge to get a Level 14 Charmander.
Squirtle (water type): Once you have caught 60 Pokemon, talk with Officer Jenny in Vermillion City to get a Level 16 Squirtle.

All legendary Pokemon locations
Search the indicated locations to find all legendary Pokemon:
Articuno: Defeat Erika, then use surf to reach the Seafoam Islands. The waters are rough, making it difficult to reach a certain area. Use the strength move on the island with two large stones to block some of the water flow. When both have been dropped, you can progress forward to reach Articuno. Articuno is Level 50, Ice type, and weak to Electric and Rock.
Mewtwo: Defeat the Elite Four and collect all badges. Then, travel to Cerulean Cave, and proceed through it to find Mewtwo. Mewtwo is Level 70, Psychic type, and weak to Bug and Ghost.
Moltres: Collect all badges. Then, travel through Victory Road and into the cave. Proceed to Officer Jenny, then use Strength to move the strength block and reveal stairs. Use the stairs to find Moltres. Moltres is Level 60, Fire type, and weak to Ice, Electric, and Rock.
Zapados: Defeat Koga. Then, surf by Route 10, and enter the Rock Tunnel. Go around the Power Plant to find Zapados. Zapados is Level 50, Electric type, and weak to Ice and Rock.

Getting Meltan
First, have Pokemon Go installed on your smartphone. The application is free and you can get a few Pokemon quite easily in the game. Once you have a few Pokemon in your collection, connect it to Pokemon: Let's Go. Once it is connected and in the Go Park, transfer over some Pokemon. Note: Once you transfer over Pokemon, you cannot send them back to Pokemon Go. Thus, make sure not to send over any Pokemon you want to continue using in Pokemon Go. After transferring over some Pokemon, you will be rewarded with a Mystery Box in Pokemon Go. This can be laid down wherever you are located, and it will spawn Meltan in your location. You will then have 30 minutes to capture Melta from Pokemon Go -- so make sure you have the proper resources to catch it. Once you have enough Melta, you can transfer over one to Pokemon: Let's Go.

Getting Mew
Connect the Poke Ball Plus accessory to Pokemon: Let's Go. At the main menu, select the "Communication" option and choose the "Mystery Gift" selection. Choose "Poke Ball Plus" to unlock Mew in the game. Note: There is a Mew inside every Poke Ball Plus accessory, but it can only be redeemed once. Thus, if you purchase a pre-owned unit, the chances Mew was already redeemed is likely. Additionally, you need internet access to redeem Mew.

Shiny Charm
Talk with the Game Director after capturing Pokemon #001-#150 in the Pokedex (you do not need to obtain Mew, Meltan, or Melmetal) to get the Shiny Charm, which greatly increases the rate at which you find Shiny Pokemon.

Catching Shiny Pokemon
To catch Shiny Pokemon, increase the Catch Combo by catching the same Pokemon in a row. The more you catch, the higher your Catch Combo ranks up, which increase the odds of catching a Shiny Pokemon. The odds of catching a Shiny Pokemon without a combo is approximately 1 in 4,096. However, your odds increase after reaching a 31 Catch Combo. Additionally, when you are trying to rank up your Catch Combo, make sure to not flee a battle, as it will break your combo. It is also said that when you do catch a Shiny Pokemon, your odds increase for finding another. Note: Shiny Pokemon seem to not appear in your collection. Thus, make a note of which Pokemon in your collection is the Shiny one so you do not end up accidentally trading it away.

Starting tips and tricks
Use the following tips and tricks to make the beginning of Pokemon: Let's Go, Pikachu! easier:
1. Version Exclusive Pokemon: There are two versions of the game: Eevee and Pikachu. In addition to having either Pokemon as your starter, you will also get exclusive Pokemon that can only be caught in the wild within that particular version. The version exclusive Pokemon are listed below. These Pokemon are exclusive to the version, but you can still obtain them through the mobile version of Pokemon Go or by trading with other players who have the alternate version.
2. Get Candy From Prof. Oak: Send extra Pokemon you catch to Professor Oak to get candy in return. You can use the candy to boost Pokemon stats.
3. Speak to NPCs: Talk with NPCs whenever possible, as they can give you helpful hints, tips, and gifts. You can also get a few free Pokemon without having to hunt them down.
4. Speak to Prof. Oak's Aide: Talk with Professor Oak's aide, who appears in different parts of the game. He will often ask you to complete a task, such as finding 50 unique species of Pokemon for the Pokdex. He will reward you with different items for completing tasks, like a bundle of Ultra Balls.
5. Easy Money: Revisit NPCs that give unique items, like Nuggets and Stardust. They will give you the item once per day, and the items can be sold to get easy money.
6. Easy Experience Points: Catch Pokemon frequently. Not only can you send extra Pokemon to Professor Oak for free candy, but you also get experience points for every Pokemon you catch. Depending on the Pokemon level and how well you caught it will determine the amount of experience points you get. This is a great way to quickly level up.
7. Pokemon Go Connection: You can transfer your generation one Pokemon to the game from the mobile version of Pokemon Go. Thus, if you have some strong Pokemon from the app, you can send them into the game. However, these Pokemon can not be transferred back. You can transfer the Pokemon through the Go Park featured in Pokemon: Let's Go.
8. Find Hidden Secrets: Eevee and Pikachu will wag its tail when your are near a hidden secret like Razz Berries.
9. Alolan Alts: To get the Alolan alternative generation one Pokemon, talk with the NPCs in the Pokemon Centers. They will ask to trade Pokemon, which give you the Pokemon Moon and Pokemon Sun version of the species.
10. No Random Encounters: There are no longer random encounters. To start a Pokemon battle, run into the Pokemon when it shows up on the screen. Also, make sure to pay regular attention to your inventory of PokeBalls so you do not unexpectedly run out.

Exclusive Pokemon
The following is a list of all exclusive Pokemon in both versions of the game:
Pokemon: Let's Go, Eevee!
Arbok
Bellsprout
Ekans
Koffing
Meowth
Ninetales
Pinsir
Victreebel
Vulpix
Weepinbell
Weezing
Pokemon: Let's Go, Pikachu!
Gloom
Grimer
Growlith
Mankey
Muk
Oddish
Primeape
Sandshrew
Sandslash
Scyther
Vileplume