So it is better to name those CEX to see if one of those fees better my needs, every time that I try to convert Fiat money into BTC I usally lost some 5% percent (Comparing the current market price of BTC againts my Fiat rate change), this may vary depending of the amount of BTC that i am buying. And always moving that BTC to another wallet outside of the exchange (Maybe this is my problem) because if I keep that virtual BTC inside the Exchange i didn't lose that amount.

I already try many varitions of this like buying BTC directly in P2P
Buying USDT and the converting to BTC and other like this.

Maybe if you name a CEX and the method used to convert Fiat in to BTC to a self-custody wallet outside of the CEX and just lossing 0.088% on fees comparing the final BTC Amount againts the Fiat amount that you use it should be VERY COOL!