I downloaded Sentinel 2A satellite images and some bands are in 10x10 resolution and some bands are in 20x20 meters resolution. I would like to convert bands with 10x10 spatial resolution to 20x20 meters and then to combine them with images that have original 20x20 resolution.
You can use the Resample tool to do exactly that.
Because you need to resample the raster to a resolution that's an exact multiplication (10 * 2), you needn't worry about spatial mismatch. otherwise, you can set the snap raster in the tool environments