You can’t make a Roblox game pass “buyable” without it being properly set up on Roblox, and you also can’t make a player own a game pass without them actually purchasing it through Roblox’s system. Roblox’s docs say game passes are one-time purchases for privileges inside an experience, while items meant to be bought repeatedly should use developer products instead.

What to do instead

  • Use a game pass only for permanent perks, like VIP access or a permanent boost.
  • Use a developer product if you want players to buy the same thing more than once, like coins, potions, or temporary upgrades.
  • If your goal is to give someone the perk without a payment flow, store that privilege in your own data system and check it in-game, but that is not the same as granting a real game pass.

Important limits

  • You must create the pass from a published experience before it can be sold.
  • Roblox does not let you “grant” a real game pass to a user outside the normal purchase process.
  • If you want the item to appear only inside your game, some developers make the monetization item in a separate experience or use dev products, but the pass still exists as a Roblox asset.

Best choice

If your project needs repeated purchases, choose developer products. If it needs a permanent unlock, choose a game pass.

TL;DR

A Roblox game pass cannot be made buyable without proper Roblox setup, and it cannot be legitimately assigned to a player without purchase; for repeated buys, use developer products instead.