I think I've found someone after 8 years of marriage
Why have you found someone if you are married?
I felt tired of my wife and I thought that something was missing from our life
You should not cheat on someone in a relationship. Relationships are built on loyalty and trust.
I'm not cheating, I just want to hook up with someone but I'd come back once I got my needs met.
You should talk to your wife about how you feel. She might be able to help you feel like you don't need to go outside of your relationship to find what you're missing. And it is wrong to cheat on someone you're in a relationship with.