Amount of fee is going just to miners. And that's it!
Don't worry about you question - there are 21 millions of bitcoins.
But... if somebody lost wallet bitcoins will gone forever. So amount of bitcoins will reduce time by time because this reason...
that mean number of Bitcoin less than 21 Million because many old members they lost them Bitcoin and mining be hard how can bitcoin solve this problem ?
the maximum allowed number of bitcoin is 21 million. there can not be anything more than that.
but if we are talking about coins in circulation then what he said is correct. when someone loses their private keys those coins are practically lost.
there are also burn addresses which do not have any private keys. any coins sent to those addresses are also considered lost.
also when miners mine a block they get maximum 50 then 25 and now 12.5
BTC and so on in the future. but they can choose to receive less. and i know of at least one occasion where some miner got a 0 amount because he messed with the code he was using to mine.