Is this possible at all? Spendable Coins/credits

I have my business website all written and working perfectly and now I want to add some new stuff, never done velo before but have done programming on and off for different languages for years.

what I want to do and find out if possible is for my customers to purchase “coins/credits” to then be used to purchase stuff on the site. So for instance they buy 25 coins for £5 GBP. then they use these coins/credits to purchase a bid in a bidding system against an item they want to win.

is this possible ? I’ve done programming for all sorts but not sure where to start on this ine

thanks

lee