How much will I learn in 4 horse lessons?

It depends on the instructor and your abilities.
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Again, there is no way to assess it.

Some people are naturals, while others take longer.

You should stop rushing, because the first few lessons will be slow. You may not even trot for the first month.

You should be in horse riding for the long term, because no matter what you do, there is always more to learn. And since you are going to a larger barn, you may not learn as much because you will be in group lessons.
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Here’s what I learned in my first four or five lessons:
At the first lesson, you’ll quickly learn how much you forgot in five years. Then you’ll learn that riding looks a heck of a lot easier than it is. The next day you’ll learn whether or not you used your legs.
Your second lesson, I’m guessing you’ll learn how generally to steer, stop (theoretically), and ask the horse to move forward with only a few tries. If you’re paying close attention you’ll learn what sort of learning style you have, and how well you learn when physically tired and/or frustrated.
Your third lesson, you’ll learn if you can do any of those starting, stopping and turning activities without feeling like you’re on a barrel that’s about to tip, or just sitting on a lump.
then you’ll relearn how much coordination it takes to actually dismount.
For your fourth lesson, you’ll learn how much of those first three lessons you retained.

As for the canter, that’s going to depend a lot on the instructor and the horse.
good luck!
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5 years ago won’t really help at all you need to get back in shape and learn how to ride again properly.No one knows what you will learn it depends on you and the instructor.
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