However, I'd like to know if there will be BTC miners once the supply is fully mined, and will the fees for sending from wallets to exchanges be high? I also wonder if the price fluctuations will be similar to the current bearish and bullish market. Currently, BTC is widely traded, buying at a low price and selling at a high price. But will BTC trading be possible in the future, similar to daily trading? I think this is worth discussing... 
When all Bitcoin are fully mined, miners will still exist because they are integral part of the Bitcoin network and without them, transaction will not exist. However they will charge their mining fee from the transaction sender and I think it will definitely be higher than what we are seeing now. Maybe there will be competition between miners which will bring the fee lower.