How do i enter the army as an E-2 with the DEP?

i was reading some stuff online the other day on how to do it, then my internet screwed up and i lost the page and i can't remember how i got to it. I remember reading like they give you a test or teach you, the enlisted and officer ranks, the military alphabet, and i think giving you a pft. don't quote me on all this because ive been looking alot lately about which mos i want, thinking bout combat engineer or technical engineer(12 or 21 bravo or tango), idk which one it is, the website says 12 and 21 for engineer/construction idk which it is. also if i go into the dep with no college credits can i go to school while doing that and get the 24? college credits and enter as an e-3 if i can enter with the above qualifications?