I don't know what that filler is - but - you can use almost any kind of paint. Understand that it won't be exactly like the rest of the wall.

First, clean it up and get rid of the more obvious lumps.

Then use a good primer - Kilz is one of them but there are others.

After that is good and dry, apply your top coat. To help it blend in somewhat with the existing paint, use your brush to lightly feather it into the old paint. The paint that you use should be the same as the old paint - that is, whether it's oil-based or latex and whether it's flat or semi-gloss.

Good luck!