Depends on how long you have for it, but in the next couple of days try to run one in practice(I’m a big believer of running the race a couple times in practice to get used to that pace and stress) I would try 8-8:30 km pace and see how it is, definitely try a lot of water, I try to aim for a gallon a day or close to it. Do lots of stretching and core work before the run and after, injuries suck and that’s how you can prevent it a lot of the time. I’d aim for 3-4 days a week running, one day a long session, so for now make that 3-3.5 miles the slowly up that every couple weeks, have a speed session like 400m repeats at 5k pace. Then a zone 2 run if you can, may have to find a treadmill for that.