Any of the good and usually US made welders are fine. I have a little Lincoln 110v unit that I've used for up to 1/4" but it really likes 1/8" or less best. I didn't have 220v wired to my shop when I bought mine plus wanted portability. I would buy a bigger 220v now, the heck with portability. Just stay away from the Harbor Freight Chinese made level junk. They are cheap, often work well for a year or so, then it's time for repairs - and parts are impossible to find. The crap Eastwood sells is Harbor Freight with a different paint job and name stuck on it so they can charge more. You also need to invest in the gas conversion. The flux core while good for welding rusty steel and outdoors with some wind and on a farm is fine, but the weld splatter makes a mess and is one additional step in a project. Unfortunately, the C25 (argon/CO2) mix has about doubled in price in the last year.

I really recommend a minimal level class. My welds before I took a few sessions of training looked like pigeon droppings, after, usually pretty good even on light sheet metal tho an occasional bird flies over "helping" the weld bead