Try and get with someone experienced shooting PRS to help you get ready. YouTube is also full of new shooter PRS vids. Being safe and having fun is your goal. You will learn a ton at your 1st few matches. Watch and learn. Ask questions, but not when they are getting ready to shoot
Since you only have 100y you may need to true your dope on your 1st few stages. If the club offers a train up before the match, go. They may open the range the day before to zero and confirm dope at distance. Reach out to the MD and explain your situation.
If you don't have one yet, you will need a ballistic solver that lets you true your dope. Garbage in garbage out, so make sure you understand how to use the solver. Something like a kestrel with applied ballistics or Hornady 4DOF is preferred, but if not in the budget get a phone app solver like AB, H/4DOF, or something you're comfortable with. Once your dope is trued (elevation) you'll need the solver to help you plan a wind hold for each target. Wind is the biggest challenge.
You can actually practice shooting stages with only 100y. Example- Set a 1:30 par time and pick 5 targets. Engage each target w/ 2 rounds near too far. Example 2- shoot same 5 targets from 5 different positions. Use paper and dots/shapes 1-3moa in size to simulate steel targets. You can also dry fire with a similar set up to practice efficiently getting into a stable(ish) position. For props to shoot off of you can use tires, a barrel, post, step ladder, etc. You can practice getting into position on a step ladder in your garage or back yard. You'll need at least one bag to shoot off of. A schmedium waxed canvas sand filled game changer is probably the most popular / most versitle bag. You'll need a small backpack to carry your gear/ammo/snacks.
Hope this helps. Good luck.