Sadly, there's currently no way to generate passive income with Bitcoin while maintaining custodial of your assets. The only way to to get income from just holding your bitcoin would involve keeping it with a centralized entity. If you do consider, you can check out either Crypto.com 's Earn platform or Binance Savings platform. They're offering as much as >= 10% for saving your bitcoin with them and both platforms have a good track record of safeguarding user's assets.
Staking isn't limited to only ERC20 tokens, You can also participate using stablecoins like Binance USD or USD tether.