Binance visa card and taxation if crypto wasnt bought on binance but moved to a binance wallet

title might be vague but i wanted a quick description to make it easy, i recently transferred some usdt from my personal wallet towards binance, mostly for exchange reasons, however i discovered their debit card and i thought i have enough usdt to buy me some stuff, you could say mostly would cost me around 500$ and also i thought why not pay for groceries with it sometimes, but what i dont understand is how am supposed to get taxed, so basically i got these usdts from a long time of trading in a bunch of exchanges/coins for a long long time and i was mostly buying coins with fiat (euros), however i dont think its possible for me to go back and track everything and figure out my total losses/gains, i definitely made profit, but not a huge profit (around 2k) total but i have no idea how to trace it back.

For context i live in france and dont really know how tax laws apply in this scenario, in short i know am supposed to pay taxes on gains, and it would be easy if say i bought 1500euros worth of btc and wihdrew when their value was at 3000euros, however in this case am seriously lost and dont know if i should be spending my crypto with the card when i want to, or if i should be paying 33% tax on every single transaction. would be really not worth it if the case is the second scenario since it would make my overall gains meaningless.