Firstly, welcome to the forum - your new home!
Secondly, access the Firewall via PC Control Center > Security > Setup Firewall. The instructions are easy to follow.
I ticked the following: Domain Name Server; SSH Server; FTP Server; Mail Server; Pop and IMAP Server; and NFS Server.
After pressing OK, I then ticked every Network Activity to be watched.
In my case, I chose Interfaces eth0 and Wifi wlan0 to be protected.
If I have goofed, someone here will put us both straight. In the meantime, enjoy your new distro.