Just to emphasize what @wireform stated. You have a suction side leak. In earlier posts it was highlighted to look at 2 drain plugs on the pump. I have attached a picture (circled in RED) what to look for. Suggest you remove them - check the o-ring - lube them and reinstall. Do not overtighten. These plugs and the lid o-ring are the only seals on the pump it self on suction side.
In reviewing your pictures again - you have a single pipe leading to your pump as your suction. I do see what appears to be a temperature probe that is strapped to the pipe. Have you knocked that or loosened it that it could be allowing air to enter. Did you run water over this part of the pipe with the pump running per the youtube video noted in post #6?
You do not appear to have any other valves above ground as the suction pipe turns downward into the earth. So if you have checked everything above ground (connections, plugs, pump top, probe) to the pump then your only option is to consider the rerun of pipe noted in post #18.
When your pump is on - can you feel in your skimmer if there is good suction?
Just one other minor point - in your original post you mention Pentair VSF pump but your signature indicates VST pump. You may want to ensure you have the correct pump noted in your signature.

In reviewing your pictures again - you have a single pipe leading to your pump as your suction. I do see what appears to be a temperature probe that is strapped to the pipe. Have you knocked that or loosened it that it could be allowing air to enter. Did you run water over this part of the pipe with the pump running per the youtube video noted in post #6?
You do not appear to have any other valves above ground as the suction pipe turns downward into the earth. So if you have checked everything above ground (connections, plugs, pump top, probe) to the pump then your only option is to consider the rerun of pipe noted in post #18.
When your pump is on - can you feel in your skimmer if there is good suction?
Just one other minor point - in your original post you mention Pentair VSF pump but your signature indicates VST pump. You may want to ensure you have the correct pump noted in your signature.
