I poked around for awhile, and maybe I just couldn't find it, but is there a way to know "how much" to lift? Right now I do a pyaramid system, where I keep going down, until I just can't go anymore, then go back up, I just recently learned about breathing and more. But is there a way to measure how much to lift?

there really is no method. depending on a 1 max rep, you can guesstimate how many reps you can do on a lower weight.

If you're still trying to figure out how much weight to lift, pyramids may not be the best thing for you. I'd recommend sticking with the basic 3 sets for 8-10 reps for each exercise. Your last two sets should end in failure between those 8-10 reps. If you can do more in those last two sets, then increaase the weight to where you hit failure at 8 reps. Don't change the weight in between sets, either. Do this for 2 months and you should have a much more accurate picture of exactly what you can lift.