How to control internet access for each program?

Hi
I would like to use a software to control which program may connect to the internet or with command “iptables”
I want to be like this -->(https://ubuntuforums.org/showthread.php?t=1188099&),But it only works on ubuntu
How to implement it for openSUSE?

I assume that you do not have many problems with most that is described there, but only want to know how to add the IPtables rule.

That might depend on you running the openSUSE firewall or not. Thus you may possibly improve your question by telling that.

I do not know how to work with the openSUSE firewall
I do not know how to use the openSUSE firewall and how to set block port or ip?
Can I do this with the openSUSE firewall?
If I want to do this with IPtables, should I turn off the openSUSE firewall?
Which ports or ip should I block ?
I want to have a secure connection,I do not want to use other software on the Internet,Just with my permission
Is there app gui (Internet Access Control ) for openSUSE?

Skimming the article but not actually testing on a machine,
I see nothing that wouldn’t work on an openSUSE if the instructions are followed exactly.

TSU

Thanks again I tried to work
I want to be the inverse (https://ubuntuforums.org/showthread.php?t=1188099&),But)
When I run this command (ni “firefox”), I access the Internet a program

Please, please, please.

How do you think we can see what you did and if you did not make any errors when you do not show us anything at all?

So, post

ls -l 

and

cat 

of all the files you created and/or changed for this.