2. Staking isn't giving huge returns but staking bitcoin or Tether with APY over 8% is somewhat profitable.
There is nothing such as staking bitcoin.
Bitcoin is a proof of work cryptocurrency, not proof of stake.
In proof of stake cryptocurrencies, you can stake their coins to validate transactions. Bitcoin is a proof of work cryptocurrency and works in a different way.
If there's a website in which you deposit bitcoin and get interest, that's not staking. That's lending.