Hip hinge angle is the angle at which you will have to bend over to grab the barbell. Depending on your skeleton morphology you could have a near horizontal back when grabbing the bar. On the other extreme you will sometimes see lifters with an almost straight upright back lifting. Most people are so where in between that angle though.
Your hip flexor is a muscle group connecting your torso to your upper leg skeleton. These help to either lift/flex your legs or torso depending on which is stationary. Deadlifts can work the hip flexors, but a better exercise would be something like leg raises, lunges, or even squats as those exercises would target more of the front leg muscles. Good luck!
Hip hinge angle is the angle at which you will have to bend over to grab the barbell. Depending on your skeleton morphology you could have a near horizontal back when grabbing the bar. On the other extreme you will sometimes see lifters with an almost straight upright back lifting. Most people are so where in between that angle though.
Your hip flexor is a muscle group connecting your torso to your upper leg skeleton. These help to either lift/flex your legs or torso depending on which is stationary. Deadlifts can work the hip flexors, but a better exercise would be something like leg raises, lunges, or even squats as those exercises would target more of the front leg muscles. Good luck!