Your posterior chain is the musculature on the back side of your body from the neck to the Achilles. With all the time we spend sitting, and all the time we lifters spend pushing, the posterior chain needs more attention than you're likely giving it. There are two specific posterior chain exercises that you probably aren't doing, or at least aren't doing enough:
There may not be a more important movement for shoulder-joint health and posture than the face pull. This exercise is remarkably effective at counteracting the effects of the three deadly S's of the 21st century: sitting, slouching, and staring at screens.
Don't think of face pulls as a strength exercise. Keep the weight relatively light and the rep count fairly high. Focus your attention on the movement of your scapulae (shoulder blades). They should retract smoothly as you pull the rope towards you. Hold the peak contraction for a beat or two.
Alternate between overhand and underhand grips from set to set, or even within the same set by doing 8-10 reps with one grip, immediately followed by 8-10 reps with the other. The difference of a few degrees of external rotation actually changes how your scapular retractors activate. Shoot for 3-4 sets of 12-20 reps.
As blush-inducing as they may be, hip thrusts are about the best exercise you can do to activate your glutes. Beyond filling out the seat of your pants, you need to maximize the strength and engagement of your glutes to bring up your squat and deadlift numbers.
A powerful backside also helps you avoid and even remedy back pain. Overcome the initial embarrassment and make hip thrusts a regular part of your training.