My pool is out by 3/4 of an inch according to the disighn on the liner but when I put a stick in and measure the depth its perfect all around the pool what's my problem is my pool out of level or is it just my liner it's a 18 round 52 in deep

Probably a slipped liner. If the water is the same distance from the rim, don't worry, enjoy your pool and can I come over?

When you put water in the liner it will stretch some so I really wouldn't worry about it unless it is causing problems

From what you say your pool is dead level and your liner is installed a bit off. Whoever installed it messed up and the fix is not easy and usually not worth it