What kind of recovery is it best to take beetwen intervals(jogging,walking,sitting…)?

Depends on your level of anaerobic and aerobic fitness.

If I´m a beginner to a sprinting but i have a pretty good aerobic base.I can do 6400m in 68 sec.with realy slow jogging in beetwen(about 4min.-4.30min)or 3800 in 2min40sec…?

Ok well when would it ever be advantageous to sit down between intervals?

What is the goal of the intervals?

For tempo, keep moving. For speed work with very long breaks you can sit or lie down for at least part of the break. Keep shaking the legs or stretching throughout long breaks.

I would like to run 400m under 50s.