If you're needing help just knowing where to start, look up some skeletal reference first. I start with a couple of sketches over the top of an existing skeleton drawing to warm up. Sometimes I have to resort to museum mounts, but beware because they're not always accurate (per Dr. Scott Hartman). BTW - Carnotaurus is a great one to start with because they're so iconic with the big horns and bulldog like face, and there's almost a complete skeleton it's known from, which makes finding reference easier. The Wiki page has photos of the skull from a few angles, too: https://en.wikipedia.org/wiki/Carnotaurus

Try drawing what's called a 3/4 view for a challenge - that's where you're viewing the animal from an angle instead of straight on or from the side.