US tax crypto

Hello everyone, I have some questions regarding the US crypto tax :)

1) If I invested 4 thousand dollars on BTC and after a year the value gonna be 8k, how much profit should I declare? 4 or 8?

2) I know that if I own a crypto (ex BTC) for more than a year I would pay less taxes when I go to sell it, but how should I deal with taxes if I buy BTC every week?

EX I own 5 thousand dollars of BTC in 2022 and for the whole of 2023 I buy BTC weekly, I arrive in December 2023 and I sell everything... in this case I would own BTC for more than a year (first purchase)... but I also bought for the whole of 2023 and so I would have a quantity of BTC sold for less than a year... in this case should I declare short term or long?

Thanks!