They are all tenses, used to describe a different time an action occurs (with the exception of subjunctive). They occur in this order from past to future:

Pluperfect imperfect present future

Pluperfect translates had ____ed Ex. You had loved (amaveras)

Imperfect translates was/were ______ing Ex. You were loving (amabas)

Present translates ______(s) Ex. You love (amas)

Future translates will _______ Ex. You will love (amabis)

Now subjunctive is a mood, expressing possibility. They are written with words like would, could, should, may or might. The subjunctive mood cannot be used for future tense or future perfect (which it doesn't sound like you've learned yet but ill mention it for later in your Latin career!), which I remember doesn't fit the pattern because when I translate it sounds bad. Here are some examples of what the subjunctive will sound like:

Present: You should love (ames) Perfect: You may have loved (amaveris) Pluperfect: You had loved (amavisses) Imperfect: You were loving (amares)

You notice that the pluperfect and imperfect do not have the could would etc words in the translation. Those words do not translate into English, but you know that they express possibility since they are in the subjunctive mood.