If you’re asking about drywall “mud”, then you’ll need to plastic bucket or tray for a small amount of mud, at least a 3”, 6” & 8” drywall “putty knives”, sanding blocks & I would use fiberglass “tape” & not paper tape.
The key is to use less mud that you think you need and work if as smooth as you can, to avoid sanding time. This is critical- as sanding later, after it dries is tedious & messy and essentially inefficient.
It will take at least 2 thin applications. If you can find a “top coat” mud it will be much easier to sand, but costs more.
Sometimes i knock down the dry high areas with my 6” knife, at a very shallow angle. Sometimes I wet sand it with a stiff block sponge. These techniques take awhile to master but are worth trying.
Agree with Cheryl's information. I would recommend expecting 3 passes at this. Also, wet sand with a sponge is superior to anything else IMO. You can find the correct type of sponge in the same area where you will find the putty knife and other tools for dry wall finishing.
If you are intending on painting, why not just paint the paneling and skip the mud all together. Use a brush to get into the grooves and a good roller not the dollar store kind to paint the paneling.