Bleach( liquid from Home Depot), baking soda( for alkalinity) , borax ( 20 mule team from grocery store and Muratic acid (Home Depot). Look at pool calculator to see how much to add. Also need basic pool test kit( Home Depot) to keep tabs on chlorine, ph and alkalinity. Lots of info about it on this site.
i have used the 3” chlorine tabs , twice to add stabilizer and will also use if I’m away from pool for a while. BBB is the least maintenance, nicest water in my experience with pools.