Hello,
Recently I started using QGIS for mapping. I found good terrain DEM map of area i want to map and successfully applied it on google maps and even menage to color height variations with Terrain Analysis (i dont know how to do it with Grass tools).
Problem is i dont have rivers. There is a way to get rivers from DEM map with r.watershed GRASS tool by QGIS but i dont know how to use it. (none of the manuals and tips i read helped)

So does someone know where i can find Hydrographyc network map just like i found DEM file and how to applay it (overlay it) ? (link to video guide would be great)
PS I need a very detailed river network for my area. Basically like every little river shown in google maps i need it. Its micro mapping

Thanks