Where do I include my wallet address after finding the hash less than target - bitcoin
Mining a valid block involves multiple steps.

To begin with, you must know which block you are mining on top of, which is specified by the previous block hash.

Then, you must obtain a merkle root that locks in a valid set of transactions. Usually, this is a set of transactions from the mempool + the coinbase transaction, such that there are no double spends or invalid transactions. These transactions are assembled into a merkle tree, from which the merkle root is placed into the block header.

The coinbase transaction in particular is important, as it must follow the coinbase transaction rules (inclusion of block height, correct output for the block reward, extraNonce). It must be placed as the first transaction in the block, and contains the output that sends the BTC to your wallet.

Finally, you must add in the other fields such as block version, time, nonce, etc.

This complete block header of 80 bytes is the payload that is hashed and compared against the target value. If your resulting hash does not meet the target requirements, you must change the nonce in the block header, the extraNonce in the coinbase transaction, or any of the transactions in your merkle tree to obtain a new merkle root, and hash the new block header. This process is repeated until you find a valid hash for the target.

In order, your approach would be like:


Get a list of transactions you'd like to include (this can be an empty list)
Select your wallet address to receive the block reward
Build a coinbase transaction that pays this reward to your selected address (plus any transaction fees)
Make the coinbase tx the first one in your list
Build a merkle tree from this list
Select the merkle root from this tree
Proceed as you're doing already