Only ADA is staking and contributing to rewards that are also in ADA by design. Some SPO distribute native tokens as additional incentives but that is not part of the protocol or represented in the reported staking rewards of your wallet.
I am not sure what wallet you are using but the value you are seeing in your wallet application for each NFT could be associated to the ADA that was used to mint, the unspent output of the minting transaction, a 3rd party service comparing similar tokens, historical values of trading it, etc.
There is no intrinsic value to any token. The supply, utility, speculation, etc largely determine this arbitrarily.
Actually the value of anything is always assigned by supply and demand and correlated to what people are willing to believe represents value. If I claim a bottle of water has a value of 10,000 ADA that is only true if you or others are willing and able to pay 10,000 ADA to acquire a bottle of water. However that’s a largely philosophical economics discussion for another time