
Depends on how old and severe it is. Pick off any dried paint and soak in soap water (I use dawn dish soap) then scratch at it from the opposite side that the paint is on. This is important because if you scrub on the paint side you may push the paint into the fabric. Soak and scratch from the opposite side and repeat until you stop making any progress. If this fails do not throw away the sweatshirt, it’s very easy to whip stitch a patch on even for beginners.
This has a decent chance of being successful but is not garunteed. It works better with less opaque colors and if it’s a very dark color like black on a lighter fabric then it probably won’t work that well because there tends to be a little bit of a faded stain left and I would recommend seeing if you know someone with a sewing kit and finding a latch.