How to stretch or shrink objects with out altering some of the parts

Carbide Create Pro does not have a direct feature for this — for doing that sort of thing in a natural fashion you will want a parametric program as discussed at the end of:

That said, one can do this in a couple of steps by working with the available tools — either scale everything up asymmetrically, then select distorted elements and re-size them to undo the distortion, or duplicate the elements, scale it, then position the originals of any distorted elements so as to replace the latter.

If you’ll upload your file and let us know what you wish to do we should be able to look into this with you.