Co-register Optical with SAR imagery

Can it be possible to co-register and STACK data of different satelite (e.g. Landsat and Sentinel 1 or Sentinel 1 and Sentinel 2) together?

once you geocoded the SAR image into the same UTM coordinate system of the optical data you can simply use the collocation tool.

If you need coregistration at the sub-pixel level you can try the GeFolki coregistration.