Killer breakdown TimeLoad. (and yes, kali is the way to go) Kali has loads and loads of tools, but it can be hard to know you already have a tool that you’re imagining, browse this for inspiration: kali-meta | Kali Linux Tools
I’d also add:
- wechall for other challenges and discovery of other wargame sites
- depending on your skill level, OTW is good for getting started and practicing fundamentals
- searchsploit (in kali), local copy of exploitdb. Most POCs included work out of the box, but I’ve run into some nerfed ones that need tweaking. Very Handy.
- To echo TimeLoad, get coding. Hackerrank has good stuff for several languages and it gives potential employers something to look at to get a feel of your skills