Hot pressed watercolor paper has a very smooth surface, while cold pressed watercolor paper has texture to it. Different brands of cold pressed paper will have a different textures. In watercolor painting, I cannot stress enough how important it is to use quality paper and paint. I always recommend using at least 140 lb. 100% cotton rag, acid free, archival watercolor paper. If you are not using quality materials, most likely you won't enjoy painting in watercolor or you will have a hard time learning to paint in watercolor. Paper is super important. I love using 300 lb. cold pressed watercolor paper, that would be my favorite paper weight. The 300 lb. paper stays wet longer, takes lots of abuse, it is great. Then there is also rough paper which has a rough textured surface.
My advice: Experiment with various brands of quality paper of at least 140 lb. or more!