I am creating a website where I want to accept Monero as payment method. I want to create a monero wallet for my each signed up user. Like say for example, when a user logs in, his BTC, ETH, XMR and USDC all wallets are created and keys are encrypted and stored in database. Further,only these wallets will be used if user wants to do anything on my website. I have achieved this for BTC, ETH and USDC. Now I want to know how I can achieve this for XMR? Anyone please help.
Just using one wallet and a subaddress per customer is the simplest path (without knowing precisely what you're trying to achieve). You can create the new subaddresses with the wallet RPC method: create_address.