I prefer Miller. If at all possible, get a 220 machine. The 110's are Meh. They work but not as well as your going to want. The Lincoln's aren't too bad. I had a small Lincoln 125 for some years until I got my Miller Matic.
The lesser machines are normally Flux Core. You will want to step up and get an Argon/CO2 tank. If you get a flux welder, make sure it can be converted. That normally means just connecting a tank and switching polarity. Flux welding works but is a bit tricky and spatters everywhere. Another nice feature is being able to load a full size spool. Some of the cheaper machines will only hold a small spool.
Make sure you get a good Helmet. I prefer not to have the controls on the outside. I tend to knock my helmet around and I would break outside knobs.
BTW
Welcome to the rabbit hole we call fabrication.
