The difference


What is the difference between ( vertex paint and texture paint ) >?

Texture paint - paints to an image texture file mapped to the object UVs
Vertex paint - adds colour to the vertices. It does not use an image or any UVs. Vertex paint can be baked to an image texture.

Can I use both in the same modeling or mesh

Sure, you can. If you’re dealing with Cycles, you import painted texture (raster image) with Texture->Image node. To access Vertex Paint you should put its exact name into a Input->Attribute node