New reader

In the last 2ish month I have gotten into comics and it feels like there is so many places to go when it form to reading different characters. I have been struggling to find collected editions to at are still in print and Interest me. For example I know it’s not out of print completely but out of stock for not the green lantern rebirth compendium and I want to read Hickman fantastic 4 but the last 2 collection seem to be out of print. Any suggestion on where to start for marvel or dc(mainly but open to others) for some of their classic characters and must read runs/books