Welcome to the forum!
First thing you want to do is get water in that pool! It appears to be a fiberglass pool and that can pop out of the ground very easily!
Next is to add chlorine. Add 5 ppm FC worth of liquid chlorine while you are waiting on your test kit.
You need a proper test kit, see
Test Kits Compared. I suggest the
TF100. A proper test kit is needed to get the accurate water chemistry results needed to follow the TFP protocols.
I suggest you read
ABC's of Pool Water Chemistry.
Post some more questions once you absorb that.