Depends on objective: improve running and do some road races§ Feel the social benefits along with improved health from persistent exercise? If so, this is the right forum.
However, if you want to race on the track or on CC course, then you must do so.
One way to prepare is to do intervals, literally break up the race distance into segments.
Interval training is so effective that those who do it correctly, or nearly so, can expect to easily beat anyone who does not. There are exceptions, of course.
Easy runs are useless, unless one means easy compared to their faster runs. To be competitive in HS, there is no point in running slower than 7:30 pace. This eliminates a lot of mileage for HS students, especially the HS fresh-soph.
Once a junior or senior in HS, to be competitive, nothing slower than 7 min/mile. Long runs should cap at 1 hour (probably 45 min for fresh-soph).
In college? To be competitive on track or CC? Nothing slower than 6:30 miles. Because CC is 10k for men in D1 (women are wise enough to only do 6k and Div III is only 8k), the mileage tends to go up substantially, concurrent with a much faster pace. This combination of high mileage at fast paces is why so many great HS runners "burn out" and why too many college coaches relied on African imports (much older runners) to run CC and to run the 5k and 10k in track.
International CC is 12k, and I've run a race or two, and that is much too long for me to race effectively. However, the older, experienced distance runners don't seem to mind racing that far.
I don't use the term 'tempo runs'. I guess that is what we used to call power runs. We would do a power run at least once a month off-season. A power run is nearly race pace for the distance run. This is very effective training, because all the runs can then be a faster pace for the same effort. However, we didn't do power runs even bi-weekly. The goal is to race fast, and once the season starts, there was at least one race every week.