"CoepI" is what is unkindly but accurately known as a "defective verb". Most verbs can be used in most or all tenses, but some verbs are only used in a few tenses. We don't know whether they ever had a full set of forms or not (the person who coined the name "defective" apparently assumed that they didn't), but, if they did, we have no way of knowing what those forms were.

It's not used in the present system (imperfect-present-future), only in the perfect system (pluperfect-perfect-future perfect). Most verbs have a first principal part which is the first person singular of the present tense. Likewise, then, its first principal part, "coepI", is the first person singular of the perfect tense. Most verbs use the present infinitive as the second principal part. It uses the perfect infinitive. There is no need to give its third principal part (usually first person singular of the perfect tense) since we'd just be repeating its first principal part. And its fourth principal part (perfect passive participle) is the same as any other verb's.

Michael's answer:

The second word is NOT from vita, -ae, f. It's from vitO, vitAre.