Have not played since 2014 have a few questions

So i havent played in years now and black friday had the full game for $30 with all expansions so i bought it. The game is WAY different now. I only played for a few months and didnt get very far but now i have more time.

I lost my main character cause i couldnt remember my password or email so i started on a second account with only a level 20 BLM and i dont remember anything i was doing like quests and all that and there is so much new stuff i am overwhelmed and i dont remember the game at all. It took me about 2 hours last night to set up my controller and mouse and keyboard then i just didnt know where to start lol.

Is there any tips for a returning player or i guess i should say new player? im wondering if i should give up the quests i got and refind some and learn how to play again. Im almost tempted to start from scratch. Everything sounds way better now though and i cant wait to see the housing

Level 20 eh? May just want to start over and let the game teach you the basics over again. The Main Scenario Quest is there for both story and gameplay teaching.
Your class will feel more fleshed out at later jobs if your concern is you aren't playing properly right now. You can also check out the Hall of the Novice around level 15 to prepare yourself for dungeons and such.

Yeah, level 20 wont take any time to get back at all really. Id start over so the story can be fresher in your head and you can grow into your class(es) more organically. However if you do decide to stick it out, now that your control setup is how you want it you can always take some time to read spell, trait, and buff descriptions(i added this specifically because there are several classes with abilities that grant you a buff status without ever telling you what that status does) to figure out what your abilities do again and how you should use them. Follow that with a short session either with a training dummy or maybe a short session of fates or something to get a feel for how your class flows again. Then ask with any specific questions you dont find an answer for.

Welcome back!
It's true there are a lot of new in game content, and I would assume that you would like to familiarize yourself with the mechanic etc, so to familiarize yourself do:
1. Talk to the novice trainer NPC in all big city inn, this will help you with job/class and get an incredible starter ring!
2. Follow through the Main Story Quests line until you hit lv 50 or 60 to familiarize yourself with dungeons, etc..
3. Once hitting lv 50 you would like to start daily roulette (why lv 50? because it's too easy now to lvl up from 1-50, but of course you can do it earlier)..
4. You can learn skills, buffs, etc from reading wiki.. Never underestimate the power of reading, this will build up your basic fundamental of each class!!

Try to "eat" the game piece by piece, and don't try to churn all information at once..

ya you guys might be right maybe i should start over , it sucks coming back after years its way to confusing. It just sucks having to level the crafting classes. Im on the fence , im gonna give it a try for 1 hour and see how it goes maybe. The battle system is different now im trying to understand

Should i bother doing all the other little quests here and there or justr stick to the story quests? also in warcraft for instance when you first come back to a new expansion or a few expansions went by and your starting where you left off they point you to the new features right away without having to look around , does ffxiv do this? im level 20 TM and it seems like the other classes i started leveling reverted to level zero.

My guy has only been to the outlining area of Ul'dah and a few other areas and of when i logged in after a few years i reverted to Ul'dah with only a few quests. What should i do? i did the golden saucer and joined a guild so what other things should i do that came out in new expansions and patches before i start questing again?

Assuming you don't have bonus experience buff, your level will be in par to the story, so I recommend to run the little quests to get extra gears and/or to maintain level. In case your level overpower the storyline, then no need to run them. BUT, there maybe some things (like materia melding) that get unlocked from the side quests..

Level will not reset to 0 if you leave the game and return after expansion. I guess you created new account hence your other classes are 0.

Stick to the main story first and enjoy the story. Don't worry too much about end game content as you will unlock them sooner or later. Most of the interesting stuffs only start when you reach lv70.. So focus on achieving that first

Also crafting is hard if you haven't unlock all area because you will lack in materials and gils to level up those classes..

https://eu.finalfantasyxiv.com/lodestone/playguide/
In this link you can find some game features that can be unlocked..