Pure Drawer

When you find code for something you want and they give you all the files, where do they go in file structure? I had been trying to find a plug in that would give me a bar menu on all devices with a push out and hoover option and I can’t find one. But I did find two sets of codes to download. I don’t know how it all goes together. Do assets go in one place and css in another? Or can I put the whole grouping of files under my child theme?
If anyone can direct me to documentation on this I would appreciate it. I know html and I know css I just don’t know how it all fits together in the back end and that is the information I am looking for.

Thanks