Hello Raghad Anas,
Taking a personal trainer course is a great way to start. Then experience working with clients will show you that not everyone is able to use proper form due to illness, injury and/or lifestyle issues. We all need to start somewhere and working towards proper form is sometimes the way to train.
Here are links to help get you started looking:
Personal Trainer ~ NAPS 2 B Fit…
The National Strength and Conditioning Assoc (NSCA) is one of the best organizations in the world for strength, conditioning, Power and Olympic lifting. NSCA also has some guidelines broken down by % of body weight for males and females for lifts like squats and deadlift, bench press, etc.
I’d also recommend an internship under a someone who works with athletes regularly in assessing and training for the complex lifts. If you’re a college student or have ties to a college I recommend contacting one of the strength coaches for a sports team.
For assessment there are lots of good videos showing how to use functional movement screening.