Comodo free fire wall

Hi I downloaded the free Comodo antivirus and as someone said it has the most features than any other
and should make some paid ones look out.

My problem is I tried to download the free Comodo Firewall and the anti virus stopped me uploading it to my computer. So I tried another free firewall and Comodo Defence stopped that.
Do I need a firewall with Comodo anti virus if so how do I get one

Hugh Williams