You can, if you get an invite since alby is swamped and they've turned off new account creation at the moment.  

 You are right to be hesitant to copy and paste your nsec.

This is why I really like the idea of a locally hosted nsec bunker. 

 You don't have to host it, try nsec.app, it's a bunker in your browser. 

 only if isntallkiwibrowser