Hi Joe,
Sounds like you got the bug. Sounds like you enjoy the sport. This is awesome.
Here's the thing. If your goal is to run sub-22, or sub-20, or sub-18, or sub-15...your first many steps really aren't very different. It's not that you can't hit all those milestones...maybe you can, maybe you can't. The thing is, you don't get to choose your ceiling. It's already been chosen for you. What you CAN do is follow a process that ensures you are likely to improve. If you're not doing most of those things yet, the gains will come quickly at first. If you already ARE doing most of these things, well, you can still improve, but it won't likely be to the tune of 4 minutes per season. Also, someone else's process is highly unlikely to work for you as you're a different person with different physiology and psychology.
Do you have a knowledgable track or XC coach? Have they given you a plan or advise or support or guidance on what to do over the winter and over the summer? If so...trust it. Do it all with fidelity. Know that improvement doesn't always come 4 minutes at a time, but improvement does come if you simply run more, run more often, run farther, and run faster. How much of those matters, but not as much as simply doing them all. We coaches like to pretend we have the secret sauce, but your work ethic is far more important than anything we can offer.
Like many teams, we had boys break the 15, 16, 17, 18, 19, 20, 21, 22 minute barrier this fall. Some of them improved by 3-4 minutes; others only improved by 20-30 seconds. There were variations to their workouts, recovery days, etc, but nothing as clean as "improvers did X, non-improvers did Y. Therefore, I should do X". I could share their training with you but without a ton of your context it probably doesn't help.