I'm living at home with my parents with everything that's going on with the virus. What should I do to get messy or wet next and what should I wear without getting caught by my parents lolol?

I sympathise.... if there is a garden maybe wait til they've gone to bed and have some fun outside with a hosepipe?

Unfortunately my backyard isn't the best because my neighbors can see into it

You could get messy in the bathroom with some shaving cream

Sugar-based substances are also good, inexpensive alternatives (assuming you have a decent drain).

A single bottle of chocolate syrup, molasses, or pancake syrup goes a lot farther than you might think (especially if you drizzle instead of dump, and is pretty easy to smuggle into your bedroom (and then into the bathroom). It also washes off pretty easily if you use hot water (and some soap once the worst has been rinsed off). Clear Corn syrup is great, too, and has less of a scent.

As far as clothes, this is a great time for a session in just some boxers or a jockstrap, which can be rinsed pretty easily with hot water, rung out by hand, and then hung in your closet to dry until you do laundry again. Or, you know, just get naked.