My brother thought so, too. His friend was a roofer and needed help. He swore to my brother that he was fully insured. Alas, my brother discovered otherwise when he slid off a roof and broke his pelvis.
If you're not going to be dissuaded, know that there is special footwear that has grippy soles to give you improved traction. They don't completely prevent falls, but I wouldn't get up on a roof without them or a harness,, especially with no experience.. DH is frequently on top of other tall structures and wears them every day. His come from Red Wing and his employer pays for them, but I'm sure there are other sources.
Finally, there are so many construction workers out of work right now that I would personally stay out of their way and let them have the work when the SIP orders get lifted.