Well I am no pro and have tons of knowledge from school but the only way to be good at it is practice. So take what i say with a grain of salt cuz i know there are better welders on here then me.
My suggestion is like many on here is start with good gear. Good helmet and PPE so you don't kill your self learning is the best start. Miller, Speedglas, Jackson and Lincoln make good hoods. I have a Jackson and a Speedglas. Love my Speedglas. Large viewing area and light. Oh and don't forget the safety glasses. I where them all the time when in the shop. Even when welding.
Not sure why John like the gas. Good to cut stuff but i was never a fan or trying to weld with it. I have both MIG and TIG and prefer TIG. More control. But for fabrication I tend to MIG more because of its speed. Not a cheap hobby but a fun one. At my work we TIG stainless. If you want to use this metal just make sure your well vented. Bad stuff to breathe. On that note be aware of certain metals that can be toxic. Like galvanize and Stainless. Bad stuff and can get sick quick.
Get yourself a good little MIG welder and just start burning stuff. If you can use a 220 machine I would go that route. I recommend using a shielding gas. Cleaner. A teacher in school always said "Just keep burnin rod brother!". Was a ironworker his whole career. There are a few techniques as far as the gun movement and I am sure everyone here does it different. Whip and pause, circles, z pattern and a few others I cant think of at the moment. I do whip and pause or circles. works best for me.
As far as settings all machines come with the basics so you can have a starting point. One thing I do know is EVERYBODY welds different. Whats works for me may not for you. Just listen for bacon sizzling and your in there. I used to look at YouTube videos during school to see how others are doing it. WeldingTipsandTricks.com is a good one. You will hear a lot of welding jargon but if you adapt these lessons to a method that works for you its a good start. I am sure once you get set up and post up picks there are lots on here that could give suggestions to help you out.
Like is said take what i say with a grain of salt. Don't want to sound like a know it all you know what. Everyone is going to have a different opinion on what is best. Like Miller or Lincoln. Soak it all in and go from there. Hope this helps.
08 TT FJC
82 Scrambler (Scraps)
81 Scrambler (Sassy)
69 Maro... next project when the Jeeps get done.....