Indie Game: Double Jump Research

With my game in mind being sort of a platform and a problem solver I thought it would be good to add a double jump mechanic due to having an aspect of  parkour/ platform mechanics. However, I have no idea of how I could achieve to create a double jump mechanic. So, I looked up some tutorials to see if it’s possible to achieve the mechanic but also to see if it’s do able. With some of the tutorials I found they were rather complicated in making them and how they were explained. Luckily, I found this tutorial which simplifies how to do it but also explain what is going on with each part. Which I found rather useful as it gives me an understanding of how it works and what’s its capable of.