Coming Full Circle is an in-game achievement in Run 3.
This achievement requires you to use the Runner to turn left four times or to turn right four times until you've gone 360° in one direction. Going right is easier than going left.
The easiest way to finish this achievement is to equip the Runner's Jack-O-Lantern costume because it allows her to jump higher.
You may wonder, how to get to the ceiling. It is easier than what you'd thought. You can just jump on the Crumbling tile path on the right, then do a long jump to the right. And voila! You are on the ceiling. Repeat this again, and you will have come a full circle around Level 35. Just be careful that since the Crumbling tiles would be knocked-off, the level may become slightly harder.
If you do not have the Jack-O-Lantern, you can use the normal Runner and still get this achievement. Go left, as that is easier with the Runner. Use similar tactics, but you will need to jump closer to the edge to get the required height.
Also, you do not need to finish the level afterwards. All you have to do is go around the tunnel, and you have the achievement. This makes the achievement easier in two ways: you don't have to finish the whole level, and if you fail on the last jump, there is a chance you still get the achievement.