I agree with ZZ.. a lil box like that will be good for sheet metal .. but nothing structural unless you got lots of time.
Start off with 'tombstone' welder.. you can usually find them at garage sales.. etc. old lincoln's ar ehte best.. usually 225a.. sturdy etc.
I use a hobart stickmate 235xl AC only.. some guys like to dc weld.. but I've found for farm projects.. a good old ac buzzbox does the job fine.
I also have a small 115v 30/70a stick welder that uses 1/16 and 5/64 rods for doing thin sheet metal work.. etc.
6011 rod is an ac buzzbox staple.. you can weld together to hunks of painted over rusty metal with it... high penetration.. not too pretty.
6013 on the other hand is lower penetration.. but with prctice.. can lay a bead almost as good as a mig.
( first 2 numbers are the tensile strength.. eg..60 thousand psi.. etc )
get a good angle grinder, chipping hammer, welding apron, gauntlet cuff gloves, a good set of various sized vice grip type tools, and if you can swing it.. an auto darkening helmet to avoid the 'neck snap' style that will likely come with your welder. get 'dry tubes' for your rod as well... also.. ALWAYS where some sort of shoe chap or closed top shoes.. preferably boots... spark/spatter likes to find ways into tennis shoes!
you will want a vice and a dedicated welding table.. and eventually a welding blanket.
this will lead, soon, to the purchase of a chopsaw at least, and perhaps a metal cutting bandsaw, maybe a set of torch bottles as well.. perhaps even a small plasma cutter if you are real lucky and havn't gotten divorced yet..
soundguy