Not sure what type skimmer that is. Some skimmers have air intake adjustment, and/or dc adjustable pump. All have gate valve (knob). Closing the knob/valve water level goes up.
Usually it takes a few days to a few weeks to break in a new skimmer to get a consistent water level. Before break in it will likely overflow for no apparent reason. Would run skimmer with valve wide open or with collection cup removed for a few days at least before you try to adjust.
With that said, with most skimmers, you want water level just below where cup attaches. The goal is thick brown collection. Tip, make small adjustments, give it an hour or so to see what it does before adjusting further
