any good training situation in any sport requires good communication.
Your trainer asks about your goals. Discuss your goals and , perhaps , your apprehensions.
Trainer should know how to prepare you for your goal, even if it is just riding at home and being as good as you and your horse can be.
Seems to me if showing was required for all students in the programs , that should have been mentioned much sooner.
But if you do desire to show, even on a local, low key level, trainer does need to know this so they can start introducing some of the skill set you may need for showing