Getting profit from a marketplace app

Does anyone have any ideas and how I can also get 5-10% of the profit when users buy an item from someone’s product on my app

app for reference - BetterFits

Okay, so my app has a marketplace where people can buy other people’s items like offerup.

Offerup has this thing when a user buys the item, offerup also gets 5% of the sale.
Idk to make a new screen or maybe even add stripe or something where It will automatically sends like 5% of the money to my account and give the remaining 95% to the seller.

or maybe I will just be the middleman for all the deals and have my cashapp or Paypal on the app, and they send me money on cashapp or Paypal and I manually pay the seller? Let me know your suggestions!!

Tu peux utiliser stripe Connect, c’est parfait pour les marketplace