Add new software which is installed in computer?

There's a couple of ways that your question can be interpreted. The first is wondering if there's a way for programs installed on the computer to appear in the PA.c menu. The answer to that is that I'm pretty sure that's not possible, but I think someone was working on a way for portable applications to be temporarily put in the Start Menu.

The second is how you install a portable application from the menu without using the built in appstore. To do this, have the .paf.exe file for the portable application you want to install downloaded somewhere, then go into the menu, press the "Apps" button on the righthand side, and then click Install a New App. Then just navigate to where the .paf.exe is, and let it do it's magic.

The last way is how to make a desktop application portable. If this is your question, there are plenty of answers in the Development threads, and an entire reference sitting in the development section. I hope one of these answers your question.

i had a problem with making pap see programs from other folder

and there is something called symbolic links

If the applications are already portable and just not in portableapps format, check here for how to add them: https://portableapps.com/support/portable_apps_suite#addingotherapps