There are many ways to measure your running distance and time. If running outside you can use a GPS watch such as a Garmin or fitness watch to track both your distance and time. Got a smartphone? Most phones these days have GPS built into them, all you need is an app such as Run Keeper to track your distance and time.
If running indoors on a treadmill, most will have distance and time tracking built into the equipment. Or you can use a Garmin or fitness watch while on the treadmill.
If technology is not the answer then another option is to ask your parents to measure the distance by car. Set the odometer to 0 and drive 1.5, 3.1, or 6.5 miles from home, that becomes your turn around point to run back home to make 3.1 miles (5k), 6.2 miles (10k), or 13.1 miles for a half marathon.
Also, most parks and nature trails will have signs that give the distance of the trail or loop.