when checking chirality for a tetrahedral, let's take carbon as an example, will two enantiomers or diastereomes of a group attached to same carbon cause chirality at that carbon, I mean are they considered different for comparing valencies and what about r/s naming , in cis trans and r/s, which enantiomer or geometrical isomer have more priority(supposing one chirality centre each) have more priority in cip?

I am not clear on how to apply method of plane of symmetry here