Learn Russian: Этого хлеба хватит.

The verb хватить (to be enough) requires the item you are measuring to be in the genitive case. It helps to think of it as literally translating to "there will be enough of this bread."

Is the verb хватит perfective or imperfective?

It is perfective. Because perfective verbs focus on a completed result, they do not have a present tense. When you conjugate a perfective verb using standard present-tense endings, it automatically creates the future tense! That is why хватит translates to "will be enough" rather than "is enough."

Since our lesson covers past tense aspects, how would I say "This bread was enough"?

You would use the past tense of this perfective verb: хватило. The sentence becomes Этого хлеба хватило. It takes the neuter -о ending because the noun (хлеба) is in the genitive case, meaning the sentence has no grammatical subject. (Note: the imperfective past is хватало, which you would use for a repeated or ongoing past state, like "the bread used to be enough").

I see a "г" in этого, but it sounds like a "v". Why?

This is a very common pronunciation rule to remember! Whenever you see the genitive masculine or neuter endings -ого or -его on adjectives and pronouns, the letter г is always pronounced like an English "v". So этого is pronounced like "etova".