Welcome, and gratz on reclaiming your old steed!

That dent in the driver's door should pop out pretty readily if you just remove the inner door card and give it good shove from inside the door cavity. You don't need to entirely remove the card, as once you pop the retainer clips around the lower edge and sides, the top edge will remain attached by the vinyl covering, so you can just flip it up out of the way. You'll prolly break some of those clips, but I got this clip kit including plenty of those and many others you may eventually need anyway:

https://www.ebay.com/itm/232800265368