1) Frequent blinking: Remind yourself to blink atleast once every three seconds.
2) 20-20-20 rule: Every 20min of screen time, look at a distant object at atleast 20 feet for 20 seconds.
3) Can use lubricant eye drops for temporary relief.
Take preventive measures to avoid spine/ joint/ posture related issues in the future - can google it.
Next Steps
If these instructions don't help then visit your eye specialist.