How do I safely power 2m 144 LED/m WS2812B strip with 5v and 10a?

Railroader:
Having a 10 Amp supply the supply likely shuts off, tries to turn on after some delay. No risc in that.
BUT! Check up the power supply manual, how it handles overloads. If it continues delivering 10 Amps things could get uggly.

Thank you, I will definitely have to check that!

Good. Here from You later.

Thanks for all your help! Would I be able to PM you in the future if I have any more questions?

In my opinion the best alternative is to write a little report just here. That will reach most people.

DVDdoug:
So for most color/brightness combinations you'll be hitting 17A for some percentage of the time, even if you're only averaging 7A.

Yes but that is what the capacitor across the strip is for. It provides the short spikes of current and smooths the current needed to be supplied by the power supply. The bigger th current spike the bigger the capacitor needs to be. That is why a large value is recommended. If you run into problems with this simply double or more the size of this capacitor.