If you're ordering off of Amazon, or another on-line vendor, try to stay away from no-name cables. MonoPrice has excellent Cat6 cables, and they sell via Amazon. Sample here: https://www.amazon.com/dp/B002RBGGG2

CableMatters, Tripp-Lite, Belkin, StarTech, etc.

Don't fall for Cat7 or Cat8 hype. They'll not work any better than Cat5E or Cat6 at your ISP speeds.