About liquid chlorine
Liquid chlorine adds almost nothing but chlorine. As it is used up it leaves a little salt behind (about 1.6 ppm per ppm of chlorine), which is harmless. It loses strength in storage, faster in a hot garage, so buy it fresh and keep it shaded.
Your target depends on your stabilizer (CYA). At CYA 40 the minimum is 3 ppm and the daily target about 6 ppm. At CYA 60 those become 4.5 and 7.5 ppm. Shocking at CYA 40 means holding 16 ppm, which takes 0.28 gal (1.1 L) from 2 ppm in this pool.
Never pour chlorine and acid together or in the same spot. Add one, run the pump for 30 minutes, then add the other.
Dosing a 2,000 gallon pool
That is about the size of a 12 ft round × 30 in above-ground pool (about 1,900 gal). A 2,000 gallon pool is usually a large inflatable, a stock tank or a small frame pool. Doses this small are easy to overshoot: one extra splash is several ppm. Measure liquid chlorine with kitchen measures you keep only for pool chemicals, and test after every addition.
Small pools also lose chlorine fast on sunny days because there is so little water. Test daily, and when the numbers drift far off it is often quicker to drain and refill than to correct them.