I've had Kontakt 5 installed on multiple machines.
Not a problem...
Lot's of decent low-cost libraries available for Kontakt
Links to many are posted here (they tend to be smaller/simpler libraries).
You can learn a lot by looking at the included content...
Kontakt is deep! Don't expect to master it quickly. You can spend years working with it... and still not use all the capabilities.
I'd read thru the manual... and start with "dissecting" a small/simple library.