Those are some very broad questions, you’re asking us how to make Counter-Strike in Unreal. Its a pretty big task, so what you have to do is break it down into small tasks and doing those tasks one by one. So to help get you started, think about this: what is a bomb? It’s a resource that can be a part of a player’s inventory, it turns into a prop when placed in a designated spot. Breaking it down like that gives you ideas on what features and blueprint classes are needed.
So one way to get started is by making a weapon inventory system and a bomb ‘weapon’. You’ll have to do a lot of thinking yourself, though. Good luck!