you could achieve a low 60 second 400m by the end of the year but your 100m speed is actually still too slow, even ignoring your not-too-great speed endurance (you should be able to at least run 32 or less right now if you pace a 200m right, that sort of drop off from 100m-200 is very very unlikely if it's not due to pacing).
To get to low 60's you should aim for
100: 13.5
200: 28
These are the MINIMUM if you want to hit 60 and even then it's highly unlikely; someone with a 28 second 200m ability will run 60 if they have highly developed specific endurance for the 400m and of course by implication have trained extremely well for the event.
400m training is basically top speed, basic endurance and speed endurance.
Ex of top speed workouts: 60m repetitions, flying 30's, 50m repetitions with 5:00+ rest
Ex of basic endurance: These will give you endurance for the 400m in general and to do the harder workouts necessary for peaking in the 400m ability. 200-600m repetitions at a pace you estimate you can run the mile in right now. Maybe 800m pace for 200m repetitions. Recoveries should be fairly limited. 200m reps should have 2 minute recoveries and 600's 4:00.
Speed endurance: 80-150m reps at 400m pace or a bit faster
Special endurance: 250-350m reps @ 400m pace: Do these once a week in the final 3 or 4 weeks when preparing for your 400m time trial or race