The best way to learn is have someone who knows tight/loose drive your kart and have them give you some feedback on it’s handling. That way you know how to correlate the feeling you have in the kart to what it’s actually doing.
A GoPro or camera is also a great tool for this. You can watch your hands on the wheel afterwards to see if you are countersteering or putting in a lot of input.
If you want to try and create handling issues so you can feel them, I would try going to full front width and running a session, then going to the narrowest front end and running a session and seeing how it feels to you.
Another common practice if you’ve got a coach or partner to help, is to put either neon duct tape on top of your steering wheel or zip-ties sticking straight up to help your coach see the wheel movement from the grid. Then they can better tell you what you’re doing with your hands when you go into the corner.