'Drinken' is used to conjugate in the present for the plural 1st, 2nd, and 3rd person (as in we, you all, they) and for the infintive (to drink). 'Drinkt' is used for the 2nd and 3rd person singular, as in you, he, she, and it. Hope this helps!
So de, het and een are articles you place these in front of a noun (substantive). A noun is someting you can see and most of the times touch. Like a door, a book. You need to learn when to use de or het, but most of the times you will feel it like: het meisje en de jongen.