Buy the biggest machine you can afford. You will outgrow a 110v machine quickly. They are good for sheet metal but struggle with anything thicker. I do all of my mig welding with an ancient Esab Migmaster 250 and tig with an Everlast tig machine. If you have access to a tig machine learn to weld with it. You have so much more control of the puddle and you can see immediately how the puddle is reacting to changes since you can see better without all the smoke and spatter from a stick or flux core machine.
There is plenty of good info here. One thing I have noticed is how hard it is to see through dirty lenses. You weld much better when you can see what is going on. The clear safety lenses in front of the shaded lens are cheap. Buy a few to fit your helmet. They are almost impossible to clean once they get filthy.