I am completely new for this hobby so I just started and put together some fpv drone. Flight Controller is MAMBA F405 MK 2 with 40A 4in1 ESC on it. 4S 25-50C Battery Flysky FS IA6B Reciever connected using PPM.

The issue is when ever I put some power to my throttle it refistered and cut the throttle and it regisrtered. But and then after giving throttle again no matter what i press the throttle just seems to stuck.

I hope its easier for you to understand by this video.

Wierd Throttle Respond (0 min 30 sec)

Hope you guys help me. Thank you

This is standard behaviour. You can't test motors on the flight controller without props. The only time you can run motors without them behaving weird is from the motors tab on configurator. Any other time, without props, they are going to behave strange.

This is because the PID controller in the flight controller is expecting things to happen when it feeds power to the motors. When it doesn't happen, the PID controller keeps adding throttle to the motor(s) in question, which in turn do nothing, and so on and so forth. It's called a feedback loop, and is how PID controllers are meant to behave.

Basically, quads act strange without props on because the PID controller is doing it's job, and the motors are not when they don't have props.

Take it outside, put props on it, and see what it does then.

its not strange behavior. it is expected.
PID loops rely on feedback to work. by not having props you are not allowing it any feedback.