I'm going to block my brother's internet connection
Why would you block his internet connection?
Because I'm tired of his bad attitude and wasting of time on internet
He is a family member and he probably needs it for certain things. You should share it with him and not block him and be mean.
Don't you think I've tried and he still doesn't comply? He's not my friend.
If you have an issue with how much time he spends on the internet then talk to him. Blocking the internet is just going to lead to him resenting you and make your relationship worse.