You show 4,400 gallons volume on the Pool Chart. Using the dimensions 20'x12'x3.5' I get 5,500 gallons in an oval pool. I'm using 3.5' as functional water depth.

Start out with 4 cups of baking soda, let it circulate and mix for an hour, test TA and pH again. There'll be a small increase in pH. Yours is too low and you could use 20 Mule team borax to raise it but with the low TA you don't have much of a buffer and the pH won't hold. Let's get the TA up and then work on fine tuning the pH.

You should test your fill water from the same tap that your hose is attached to (not from a tap that may have a water filter on it). Test for chlorine, pH, and TA.

Instead of baking soda you could use washing soda. It will raise both your pH and the TA, and both are low in your report. 8 oz (1 cup) of washing soda in 5,500 gallons might raise the pH to approximately 7.3 and will raise the TA by approximately 10 ppm. If your volume is 4,400 the numbers are 7.4 and 13, respectively.

As to the slow dissolving CYA, the faster way is to use liquid stabilizer but it is very expensive. You can put the CYA granules in the skimmer with the pump running and it'll disappear faster but that doesn't mean it's dissolved. It just means it's now sitting inside your filter dissolving slowly.

Let us know how you did with the baking soda and we'll take it from there.