How Do Attackers Forge Bitcoin Blocks And How Do You Identify Forge Bitcoin Blocks?
I assume that when you say an attacker can forge blocks, you mean that a dishonest miner can create invalid blocks.

The answer is no for a very simple reason. When a miner's bitcoin node (the computer which runs the bitcoin software) creates a block, it must follow all of the consensus rules. Let's say, for example, he tries to create a coinbase transaction with 13 bitcoin, plus fees. Note that, at the time of writing this, the block reward is 12.5 bitcoin.

Then it finds Proof of Work and sends the block to the rest of the network. Every node that receives this block will first check if it follows the rules. Since it doesn't, the node will reject that block. Therefore, it will not get included in the blockchain and the miner just lost the reward.

So, every node validates everything on its own. No node trusts information it recieves from other nodes.