Head on over to the
APUG Plate Camera forum for loads of useful info.
The type you've shown can shoot glass plates, or sheet film. The plates go directly in the holders, whereas film goes in a sheath that goes in the holder. If you can't find the sheaths, you can use some low tack adhesive on the glass plate and stick the sheet of film to the glass. They typically just have front rise and fall. A few may have a coupled rangefinder, but most don't, and there are a couple with interchangeable lenses.
There are various sizes of holders, and various mount types (there was no standardised system), so if you do get one, make sure it comes with some holders. The most common sizes are 6.5x9cm, half plate, 9x12cm and 10x15cm. 9x12cm is probably the easiest to get hold of, and just a wee bit smaller than 4x5".
I've got a ZEH Zeca from the 1930's that I use occasionally. It's good fun to use, and a fairly light weight "small" large format. I've shot mine handheld as well, using scale focusing and the small finder for rough framing.
Here's one shot I took with mine a while ago:
windmill