I read them in the old “Essential” line, which is all black and white but used to be the cheapest way to get a big collection of comics. You may be able to find them in used book stores still, but they are getting rarer. (example: Essential Amazing Spider-Man, Vol. 1 (Marvel Essentials) https://www.amazon.com/dp/0785121927/ref=cm_sw_r_cp_api_glt_fabc_ACX6YDCVBNGWSAMS8106)
Great inexpensive way to read the classics.
I will admit that I instinctively check the wikis, but it is always good to have some first hand knowledge.
I like to think that there are two approaches you can take to reading comics:
I know it sounds old fashion but you should try your local library. They'll probably have a lot of comics you can read in collected editions and volumes. And you can't go wrong reading the original sixties comics like this, this and this, so that when those "X character wasn't like this originally!" arguments, you'll be able to chime in.
Also I should note that you should get a marvel unlimited subscription. You'll save a ton.