Both ways you describe work, you will not be 'wrong' either way.
A drill plants a bit better, places the seed about the right depth, and closer to moisture if you are in a drier period. So that is the 'proper' tool for best results.
We try to harrow after using a drill, just to level the ground better, and cover any seed that didnt get covered. But it is not needed, you will have good results without harrowing.
With a broadcast seeder, you need to go over with a harrow in loose ground. Or a bit more aggressive with a light disking or field cultivator in hard ground, to get most of the seed covered up. It is common to plant a tad havier with a broadcast seeded because one figures not every seed will end up the proper depth.
Again, both ways work fine, no right or wrong. Get so e rain after planting and you are good to go no matter how you do it.