My bike has a front brake.

By trial and error I discovered the best method to brake quickly is to apply the front brake to reduce pace and then use my legs by apply back pressure.

is that the best non skid method to brake?

A few observations,

No matter how well I execute my plans I never stop as quickly as I do when using my road bike which has okay but not great rim brakes. Is that to be expected that fixed gear braking is slower than front/read rim brakes?

It feels I'm going to twist an ankle some times. Is that ever going to happen and I should be aware.