1600m/1 Mile Training

[Deleted User]

For me, speed isn't a problem however keeping that speed is always a struggle and when it comes to the mile, I never have the endurance to run a good time.

For a quarter-mile I can around 5 min/mile pace but I cant even run 3mins for 800m/0.5mile

What workouts would you recommend for a 15 year old?

I don't have access to a track by the way...

Any help is appreciated..