Gaude! Latin doesn’t have any accents - they are just there to assist a beginning learner with pronunciation.
They are called macrons and tell you whether a syllable is long or short. Very handy when you are writing poetry, but otherwise not all that important really.
Well… Latin does have a stress accent, though you will rarely ever see the accent written down. The rules for accents of verbs are the same as for all other Latin words; these rules should be detailed in the first sections or introduction of any textbook. If you are referring to the straight lines over some vowels, as Kasper assumes, then you are indeed talking about macrons and not accents. Sometimes (just to confuse things) writers do use acute accent marks to represent long vowels.