I would raise your pH by 0.4. Do you have 20 mule team borax on hand? If so use it and pool math to raise pH by 0.4. Test pH 30 minutes later and report pH.
If you don't have 20 mule, test pH tomorrow. With a TA of 120, your pH should rise naturally. If it gets into the 7s, then don't add 20 mule (except below).
If still in the 6s tomorrow, get some 20 mule team borax and raise pH by 0.4.
As to next steps, that is to SLAM the pool. You need the K-1515 to SLAM.
You can add 3ppm per day of liquid chlorine, nothing else.
You can also add 30ppm CYA to the pool in prep for the SLAM. Use the sock method. After it is soaking for 30 minutes, start squeezing the sock...it should dissolve fairly quickly. When the sock hits the water, then switch to adding 5ppm per day until the K-1515 arrives. (Add either 3ppm without CYA or 5ppm with the sock in the water...don't add 3, then add sock, then add 5ppm...make sense?)