how to model this stone tower in blender _ blender non destructive modeling

[@AlexeyNapechkin]

4:26

[@thomas7726]

Hi, taking advantage of this video, I’ve always had a problem with 3D modeling:
How can I place arched doors and windows on a cylindrical tower like this? Especially using subsurface...
It would really help if you could make a video about it!
I know how to create an arched doorway and then add a straight wall around it, but I can’t "sculpt" doors and windows like that into an already-made cylindrical/spherical mesh. Not with a good topology haha

[@CG_VOICE]

don't use subd modifier in architectural modeling. to create large scenes. use subd modifier for detailed props, or bake high poly to low poly