Ok, so in most obbies, there is a GUI that allows you to reset your progress. That means that when you click it, it will set your stage to one and make you start from the beginning.
What I know:
The code will access leaderstats and set the stage currency (Stage) to 1.
It will teleport the player's character to the first checkpoint. I can do that.
It will set the player's health to zero, simple.
I would seriously appreciate some help as this problem has actually put a lot of my projects on hold because I like releasing finished projects.
I have attempted to code this, but it didn't work. Maybe a few hints as to what I should do would help.

5 comments
At least make an attempt at this before coming to here to ask for code. We aren't supposed to just let you ask and provide you all the code you want.
I did make an attempt, it didn't work. Sorry for not stating that, I'll edit my question.
Well we can't just hand code to you .-.
Show me your code and I could point out what you may have done wrong and show you how to fix it.
mk