Chemicals for above ground intex pools?

I have 15 x 48 intex ( 4,400 gal. ) pool I set up last night and started filling it about 1 a.m. I was planning on adding a stablizer first before the chlorine but I found out that my stepson put the little floater in the pool that holds the 3" chlorine tabs is this good enough or do I need to do something else with it. Also last week I had added a shock to it but the water was milky afterwards ran filter for about a week it didn't help so I drained it as you see. I was also told that there are 2 different kinds of shock 1 for vinly pools and 1 for built in pools