How to get back token from a contract holder


I created a token, and I sent 8B to the contract address of my token, how can I get back those 8B ?

When I write in the contract in the transfer option and I put my wallet address, it doesn't do a transfer from the contract to my address but from my address to my address,

Can you include the code that is supposed to send the tokens back to your account from the contract?

From what I heard, it's with the withdraw function, but the withdraw function is not in my code,

I heard that even if it wasn't in my contract, I should be able to add it, do you know how can I proceed to add it ?

Share the contract address with code verified in etherscan or the contract code