GUI and stuff

So I created a healthbar (finally), that even works….well, kinda XD it’s decreasing it’s value over time, I can also reverse it, but I’m still looking for a good way to measure when and how often enemies are damaging the dragon and I have not yet fully grasped how I can use time.deltatime in every occasion.
I’m even starting to think, that I maybe should create some kind of universal timer, for the whole scene, that I can access in my scripts, instead of creating new methods for every time I need some kind of timer.
It’s going forward slowly, but sometimes I really wished I could be faster and knowing what I’m actually doing, but hey, thats exactly what I’m learning for, so that some day I can actually make such things, without needing to struggle so much with syntax and possibilities that I’m simply not aware of atm.

That said, a little screenshot of my current GUI: