To assign the brush tips from ABR files you have to go into Krita’s brush editor, you’ll find it via the icon with three lines that have a dot in front and above these three lines is a wavy line.
In the brush editor, you should begin to study existing brushes that have similar characteristics like those you want to recreate.
But honestly, if you just begin with Krita, it may be better you familiarize yourself firstly with Krita itself before you begin trying to recreate PS brushes in Krita.
Furthermore, there are so many brushes for Krita that there really is no need to recreate brushes from other programs.
I’m just in a hurry, so I only give you a few links, but if you use our forum search for topics with ABR and my username you’ll find 50, 100 or more postings where I discuss this topic, just search for ABR @Michelist or vary the search term:
And via this post you find lots of brushes for Krita:
And this forum category gives you access to even more brushes:
Hello @MadmaxNeo and welcome to the forum!