Proof of stake coins are designed to give interest to users who hodl for certain periods, these rewards are a product of the network protocol and users would get it by simply keeping their coins in their wallets.
Bitcoin is a proof of work coin, so you'll not get any interest for hodling in a non custodian wallet.
Somehow in my exchange account I get staking rewards over my BTC.
Some exchanges offers staking rewards to users. This is not a protocol design, but a service rendered by a centralized exchange.