Help Understanding MMOs

NOTE: This was intended to be a YahooAnswers question, but because Yahoo Answers is crap, and my "details" were 1824 words too long, I'll just post it here. I apologize if there is any weird context in this, and if it doesn't belong on these forums at all. Thank you!

Hi! I'm a gamer and I hate to admit that I don't understand MMOs that much, even with their tutorials. And NO, I am not an FPS person, I am an RPG fan. I have been playing RPGs for a very long time and I am a veteran at League of Legends and Smite. But there's just one problem with RPGs and MOBAs: you can't play it well with friends. It'd be impossible for the regular RPGs I have like Final Fantasy to have multiplayer modes, and in MOBAs, even though you CAN play with friends, I am DONE dealing with trolls and toxic people and others of the sort lol. So, MMOs are the perfect solution. Me and my friends being a team, not having to majorly deal with other players (we don't plan on doing PvP in MMOs) and just to have fun. But, I just don't understand them. So it's not really the combat that gets me. I'm OK with combat. I know all about damage and abilities and Mana and Cooldowns and things like that because, well, I've played played MOBAs before, which have a similar control scheme. It's mainly the way you improve yourself in MMOs. So you have experience points and gold, of course. One of the main problems I have is loot. I get all of this loot, and I don't know what I should keep or what I should throw away, because I don't know what half of them do, and the other half are potions and equippable items. And because of this, I run out of inventory space and I have no clue what to do. Another problem I have is buying things. Whenever I'm in these MMOs there are like 5 trillion shops and stores that sell different kinds of things. Like, I don't even know what 75% of these shops are trying to sell, and I don't know where I should go to spend my gold most efficiently to improve myself with items. Another problem I have is the itmes themselves. Like in Neverwinter, you have regular equipable items, of course. But then you have like crests you can add to the items and you also have crafting and trading and gardening and UGH TOO MUCH! But I don't care if it's too much, I just really want to understand it. Also, EVENTS! When I play in a MOBA, I want to be part of an event, but I don't know what events there are and aren't because they never tell me. Ok, yeah, they DO tell me events like in the patch update screen before you actually get into the game, but that's it... I don't know how I should take part in the event or anything else and what kinds of awards I get. Finally, customization. I love customization, and I don't mean like how I want to build my character, but like how I want to stylize them. I see all of these advanced players with stylish characters jklsgsvmklthltdkbj I wanna do that too! Please, I'm sorry if this is a lot lol. I hope I don't come off as a Noob, I just really want to understand MMOs. Me and my two friends (yes there are only three of us and we're gonna just be a party for our entire lifetime in MMO(s) if we actuially understand them) have a LOT (I mena a LOT) of time on our hands and we'd definitely be willing to learn more about MMOs. Anyways, you don't HAVE to explain EVERYTHING I JUST ASKED. If you can find a guide or something online and send me the link, that would me GREAT. By the way, the MMO we're setting our eyes on to play is Neverwinter, so if you just answer my questions with Neverwinter, that would be even better. :) Thank you!!!! :)