It is possible to change the game's FPS to whatever you want. Just use the "area speed" command. If you want, you can go to Game Setup>Other Settings>Every Area Command Prompt then type in, "area speed = 60." It's just saying the speed is gonna be 60fps.
BUT, please note that there are downsides. While you can use 60fps, you will have to re-work all physics for everything for speeds to work properly.
I've talked with TingThing (PB's developer) about making it compatible with 60fps from the start, but it would be a back-breaking job. Because he'd have to re-write all physics for the FPS to increase to 60. So you have to manually do it yourself. Since you probably haven't worked with any projects in PB hardly at all, it's gonna be easy for you. As for me? I've been working on a game since the beginning of 2018 in PB, but it would be extremely time consuming to re-write all physics. So, just know you'll have to re-do everthing's physics for everything you create for 60fps to work properly. If you don't adjust physics, everything will run way too fast.