Yes. A calendar month can be from a date in one month to the corresponding date in the next month, so the 20th to the 20th of the next month qualifies as being a calendar month.

Next month, the month after this one, 1 month from now, a month from now, or the month that follows this current one.

There are approximately 4 weeks in one month. It averages out that a month has exactly 4.34812 weeks.

The first month birthday of a baby is often referred to as their "one-month anniversary" or simply their "one-month birthday."

You can ask "Which month comes after this month?" or "What is the month after this one?" to inquire about the upcoming month after the current one.