You sound a bit like me. If you can already "solder" (i.e. soft solder), you
can learn to braze (i.e. silver solder) with a decent sized (plumbers type)
propane torch. You need to get the metal up to red heat so you will need to
surround it with insulation bricks and/or sheet. I've done stuff like this
with bricks. You'll need to read up on fluxes and rods, but plenty of info
out there. Or you can more or less teach yourself simple MIG, I find the
gas-free "cored" wires are fine for the sort of stuff I need. I can't do
anything pretty, but you can get the visible side OK with an angle grinder
and car filler and paint. I wouldn't try and do anything load carrying where
a single weld failure could cause serious injury without training.