Help with Windows 10 activation

Ok here is what happened. I got the update to windows 10 on my computer then I found out how to put it on a flash drive on I put one on the flash drive and then I upgraded my computer to windows 10. So anyways it was going well and it installed Windows 10 then it restarted to a black screen, so I just left it there for 10-15 mins and it was doing nothing so I booted on the hard drive and it would not boot into windows 10 it just said launching startup repair but that did nothing but I couldn't boot into windows 7 or windows 10 so I could do one thing which was install from the usb flash drive. So I installed windows 10 and when it got to product key activation I just skipped it. So finally I got to the windows 10 desktop and I tried 3 different product keys so I am stuck here with a non activated Windows 10. So I would like to know how to activate it or am I screwed. Thanks

Wait!

Microsoft has been overoptimistic that it can handle the volume of new Windows 10 users, and there are problems with Activation.

It does not say anywhere that I have seen how soon you need to activate before your installation goes into some form of nag mode.

There is an annoying feature that stops you personalizing Win10, but most other things work reasonably.

If you want to use an existing, or create a new Microsoft Account, and log in with that, that may give you access to more help, when Microsoft get their feet back on the ground.

Make sure that you allow automatic updates, because there are plenty of bugs to fix.

Ok I have a another question. Now I have a working product key but when I hit activate it said Windows cant activate. Try again later. What does this mean.

Ok how do you do the Windows Store License Verification Task

Ok what does Windows cant activate. Try again later mean?

Keep trying to activate, it took a while for one of my machines to activate.

ok ill try