I am taller, have a lower desk and work long hours at a desk, resulting in neck, shoulder and lower back pain, how can I solve it?

Raise the height of your desk, lower the height of your chair, look flat or up at the computer screen instead of looking down at it, and walk around and move around after 30 minutes of work. Pay more attention to functional training of the neck and shoulders during the day to increase the strength and stability of the core muscles in the neck and shoulders, and swim more if you can.