how can I get the fee percentage on buying or selling a specific amount of bitcoin at any time?

[Bitcoin]

how can I get the fee percentage on buying or selling a specific amount of bitcoin at any time?

so im noob on all of this so bare with me.

im trying to test the possible net revenue of a trading algorithm/bot,
but i dont trust it enough to test it with real money, so im going to simulate how much money it would make, by finding out the transaction fees for each buy/ sell.
now ive read about it online and all i seem to find stuff like :

https://bitcoinfees.earn.com/api/v1/fees/recommended
output:
{ "fastestFee": 40, "halfHourFee": 20, "hourFee": 10 }

which seems to be in satoshis per byte,
so if i wanted to buy 1 btc at that time, how much would the fee be ?
or is there another API or service i can use ?
thanx

Source: how can I get the fee percentage on buying or selling a specific amount of bitcoin at any time?