I'm new to blockchain and bitcoin. In my understanding, miners are trying to find a nonce that is added to a block, and then the hash of the block will have some zeros at first and the first transaction in each block is a coinbase transaction.
Is coinbase transaction added to block before calculating the hash or after??? And what forces the miner, not to add 100 bitcoins as their basecoin transaction??
Also on btc.com I saw that different blocks have different amounts of bitcoins. Shouldn't it be a fixed amount of bitcoin, i.e 6.25??