For showjumping, keep going to lessons for now. At times, you might have to change instructor to go up another height, but most instructors can teach up to 1m.
If you're not already, start working at yards. Accept riding anything that's asked from you (unless it's crazy). Even the laziest of cobs can teach you something new.
Once you're competent at jumping around 1.20m, you've a better chance at finding a job as a rider for a show jumper, however, don't neglect your dressage and flat-work.
Take your time, and become good at what you do. Most people, especially at a higher level, can tell the difference between someone who's used to riding school horses and are barely sitting on, and people who can ride the horse.
When you have more experience in the industry, it might be easier to decide on what you want to do.
I have been never showing but I jump 70cm
Finding a job with showjumpers is very easy. Most of then advertise on Facebook now, and there are a few recruiting agencies. What level is your current showjumping?