Yes we can offer selection of colors as while as sizes for apparel on your store. We can do this by adding option as well as sub-option. For example, Option could be Blue T-shirt while Sub-option could be various sizes like S,M,L,XL of Blue T-shirt.
1.Go the stock>select the option add a new product>scroll down.
2.Then select the option given below to change your product size.
3.If you want to change the color of the product select from option below of add only option and select the colors.
4. Select the save product option.