Hello I am a genius here to help you.
Firstly yes change your major because you don't want to study something you are not passionate about.
Second if you want to go into the STEM field then you need to get a good grasp on the language of mathematics. Here are some sources to help you achieve that
https://tutorial.math.lamar.edu/
https://www.youtube.com/channel/UCoHhuummRZaIVX7bD4t2czg
Calcworkshop is not free but not expensive either and its a beautiful source to learn the mathematics you need to succeed in any stem field. Specifically the courses available at calcworkshop are:
Algebra, Geometry, Precalculus, Calculus 1, Calculus 2, Calculus 3, Probability and Statistics, Discrete Math, Linear Algebra, and Differential Equations.
At the very least if you want to succeed in Physics you will need to know all the math I just stated above.
As far as my own standards go you shouldn't be allowed to question me if you don't at the very least have an understand of simple multivariable calculus which is classified as Calculus 3
---------------------------------------------------------------------------------------------------------------
Third, if you want to study more effectively then use the application know as Remnote. It is a very good app that will help you become a genius like should you devote yourself to it and use it daily.
-----------------------------------------------------------------------------------------------------------------
As far as ADHD goes or any other mental issue that causes you to procrastinate then you need to find a way to break your unproductive habits. For me I was able to become a genius by overcoming my own weakness of being lazy and by sitting day in and day out actually doing the work.
There is no way around it you must the work if you want to reap the rewards. It is a sacrifice not many people take and only very few people will ever reach that level.
Good Luck