My 93 caravan the hood latch won't catch to keep the hood closed

Your hood latch probably isn't returning to the right position for it to catch. This is commonly caused by one of two problems: (1) too much hardened grease and crud on the latch itself is keeping it from operating freely; or (2) the hood release cable has gotten rusty or kinked over time and is no longer releasing completely.
I would suggest testing the hood release cable before doing anything else. It's an easy test and it only takes a minute. Enlist the help of a second person to pull the hood release lever while you look at the hood latch. When your helper pull on the release, you should see the cable pull part of the hood latch. When they let go, that part should swing back to its prior position. Using a long-shafted screwdriver, see whether you can "help" that moving part move any further on its return path. If you can push the latch any significant amount, it's not returning all the way to its proper position, and your hood release cable is probably binding.
In the short term, if you manually push the hood latch back into position, you should be able to close your hood again. However, you'll have to do this each time you open the hood. In addition, you run the risk that, not too far in the future, your hood release cable will actually completely bind or snap, and then you'll have a much harder time opening your hood to replace the cable (or do anything else, like add oil or washer fluid).