When you get the fixed retainer do you have the lip retractor in your mouth and suction?

Yes: If the orthodontist is bonding a wire to your teeth as a retainer , he will probably use a retractor and suction to keep the area dry from saliva or water.

Yes: Your teeth must be kept dry for the adhesive to stick to your teeth. You must also breath through your nose during the procedure. Your breath is wet and will compromise the adhesion.