Hello,
First of all, welcome to this world!
Then, you don’t need “hacking tools” to do these challenges. I’d prefer advising people to make their own stuff to pass levels as they’ll understand everything behind levels (except for some hard levels like captchas where beautiful tools are available).
Now for Kali Linux, free to you to make this choice. As for me, when I started, I’ve downloaded & installed a simple ArchLinux OS & installed things I needed by myself because I liked the fact I could customize it like I wanted.
The best way to know what are the best tools for CTF is to do challenges and find by yourself what tool suit your requests the most.
Here’s a little link with a lot of interesting tools that might help you ; https://github.com/zardus/ctf-tools
If you still have any questions, feel free to ask ( or to PM me :) ).
Have a nice day!