NDA's are very common in my niche (writing & translation) and I've signed many.
1. Upwork Contract FIRST
2. Then, and only then, sign NDA (no personal info beyond email required)
Work smart, work safe and best of luck to you!
I also sign NDAs often, sometimes in advance of a contract, so the client can share proprietary information so that I can scope the project. It's entirely reasonable and appropriate. (Never sign anything that includes a non-compete clause.) I don't mind providing my mailing address and email address. Re. the latter, I actually make it a point to exchange off-UW contact info (email & tel no) with every client and strong prospect, because the UW message center tends to go dark at the most inconvenient times.
The real red flag in your description is "I can't get access to a file that would test my abilities to do the job before I actually get the real task to do." I hope that was going to be a paid test, as it's against the ToS for the client to request or require free work.