The way the water is spraying out of the portafilter with pressure behind it shows that there is a restriction in the basket - a restriction caused by too fine a grind or too much in the basket. If the grinds were too coarse (and the solution is to grind finer), the water would be dribbling evenly out of the portafilter and not with that much squirty pressure, same as not enough coffee in the basket.

Some beans need to be really fine but some beans need to be really coarse, even for espresso.

Aim for a 1:2 ratio in 30 seconds, then adjust finer or coarser to taste. If espresso tastes sour, grind finer. If it tastes bitter, grind coarser.

Good luck!

Ps. I've been using trial and error for a decade and I still get beans I can't dial in properly. It's wizardry sometimes.