My brother in law has since bought some shiny new brewing kit including a boiler, mash tun, hot liquor tank, chiller plate etc. Having done a couple of brews with him I now have a tiny bit of experience and thought I’d dig this out in the hope I may understand more what I’ve actually been given. I still don’t really understand what I’ve been given

To me it looks as though it’s some form of kettle, does this perform the task of boiling the wort? Or does it look as though it may be used for mashing and boiling too? The fella that gave me this kit years ago I’m sure he mentioned something about a thermostat that I would need but can’t remember now what he actually meant or where to look for the right part.
Could anyone help me here?