Here's a list of all minigames in this game and where you can play them.
Toylet: (Sotenbori Sega Arcade only discovering it in chapter 2 onwards by talking to Machida outside of the Club Sega. After you talk to him it will also unlock it in the Club Sega in Theatre Square. Best played by limiting your max fps to 30 to make the challenges for Milky Nose easier)
UFO Catcher: (It's in all Club Sega locations and the Batting center)
Virtua Fighter 2: (Any Club Sega)
Virtual-On: (Any Club Sega)
Batting Center: (Yoshida Batting Center Hotel District of Kamurocho)
Casino: Blackjack Sotenbori location Yotsudera Kaikan casino, a building in the southwest area or inside the dragon palace in Kamurocho after you complete Substory #22: To The Dragon Palace
Casino: Poker: Same place as blackjack
Darts: Location: Club SEGA Theater Square in Kamurocho, Shot Bar STIJL in Sotenbori
Gambling Hall: Koi-koi: same place Blackjack only exception is for Sotenbori in Yotsudera Kaikan casino the hall itself is on the first floor, entered via a corridor in the north
Gambling Hall: Oicho-kabu: Same as Koi Koi
Golf Center: Yokobori Golf Center on Sotenbori St.
Gravure Photo Shoot: Gravure Studio "Fascinant Jardin" in Kamurocho can be started as early as chapter 1
Karaoke: Karaokekan in Kamurocho, Karaoke Snack Bar in Sotenbori
Mahjong: Lullaby Mahjong in Kamurocho or Riichi Towers Mahjong in Sotenbori
Shogi: In Kamurocho, a Shogi player hangs out in the abandoned convenience store in Nakamichi Alley. In Sotenbori, a shogi player sits with others south of Four Shine during the daytime.
I don't remember if these counts but I'm gonna add them anyways just in case.
Bouncer Missions: Kamurocho Club Debolah in Theater Square during Chapter 5, you can go to the east side of Theater Square and speak to a young fellow looking for bouncers. Do his substory and you'll unlock the activity.
Cabaret Club Grand Prix: Can be found late into chapter 4 while going through the story in Sotenbori at a place called Four Shine.
Majima Construction/Clan creator: You will run into this late into Chapter 5 through the story. It is located in the top right part of the map where the homeless camp was at in Yakuza 0 and Kiwami 1.