HI-- is it generally safe to make global rules with highest prio allowing all incoming connections from home network (192.168.x.x) and counterpart all outgoing connections to home network?
it does not matter if home or web. security means limiting programs to address and port as needed. ofc this is not possible for a browser thus it needs some added security as an ad blocker or similar. but even this is simple: port 80, 8080, 443 and for dns 53.
Guess you haven't been keeping up with all the press releases on SMB vulnerabilities? First, you need to describe what you want to accomplish. Is this a stand alone PC and you do not want anything on your established local network being able to access the PC? Is so, then you want to first set your firewall to its Public profile. Note that in most firewalls this will prevent sharing of any devices including printers that are attached to you PC.