Basic routine
Monday 200s with 200m walk recovery. For the amount of reps basically look at when you want to be peaking and that week should be a set of 3 at close to race pace. Every week prior add 1 rep and about 1 second. So say you want to aim for 50 second 400. That last week will be 3 200s at 25 seconds. 7 weeks prior will be 10 x 200 at 32-34. Ideally you would start 12 weeks before and 15x200 @ 39-41 to ease into it.
Tuesday overdistance. 3-4x800 with full recovery about 8 minutes. Should be run at a pace that is uncomfortable, but able to be maintained throughout the workout. Two weeks of this then 3x600 getting faster than the 800s with same recovery. Two more weeks then 3x500 and the last couple weeks will be 3x450 full recovery.
Wednesday rest
Thursday speed endurance day. Can also be hill repeats at start of training season 80-150m should be enough and aim for 8-10 strong reps with walk back recovery. 3x45 seconds at race pace. 50 second 400m would try to hit about 350-360m towards end of season. Full recovery
Friday rest
Saturday: Race
Lifting schedule should be thrown in as well during the week. Two days of leg work and 1 day of upperbody. Aim for 10 reps of everything at a relatively easy weight to ease in. Focus on developing proper form vs max weight as a beginner. Abs should also be thrown in regularly.
Basic leg day:
Squats (back or front)
Cleans (Power, hang, or snatch)
Step ups or lunges
Hamstring Curls or Romanian Deadlifts
Basic arm day
Bench (flat, incline or decline)
Back (Machine row or bent over single arm row)
Shoulders (push press, single arm dumbell, etc)
Pull ups (Front grip, back grip or runners grip)