Is it possible to have hypothyroid and after taking meds for it then it can be corrected and no meds needed after that? Or life long meds?

Yes, it is possible. Transient hypothyroidism occurs. Some conditions cause thyroids to malfunction temporarily, and in those cases, the thyroid will recover on its own and you will not need lifelong medications.
Hypothyroid. Usually, when it's diagnosed, it's predicts a permanent condition and you should take replacement thyroid hormones for life. In the past, many people were inappropriately treated for this (eg to lose weight, low energy, etc). In these latter cases, sure, it can be stopped and thyroid levels should be repeated in 2 months to confirm you are normal.