It’s pretty easy to create a basic combat system your self, and it’s a great learning experience. Just add small features, watch tutorials etc. I can recommend these youtube channels:
https://www.youtube.com/channel/UCRn…pXA0lccx_U1mww
They’re great! 
To add features like vaulting over objects, dodging etc, check out Root Motion for Unreal. All you need is an animation and it’s done for you!
If you really want to add a combat pack to your project instead I would suggest that you contact the person you purchased or received it from for help, they’ll either have tutorials or love to help out! That’s the best part with the indie gaming industry, people really want everyone to succeed.