Curiosity: Is your class is using B4A or are you using B4a (on your on volition) for the class project? Does the teacher want you to use a library or come up with something from scratch?
As a month has 31 days max., just add 31 labels to the activity. Start with the current month and use a loop to fill the labels. Start with 1 (first day of the month). Use the date functions: https://www.b4x.com/android/help/core.html#datetime to add 1 day for the next day and so on. If the day changes to 1 again, stop (exactly: September has 30 days. If you add another day with
B4X:
DateTime.Add(DateTime.Now, 0, 0, 1)
the sequence ist 27th, 28th, 29th, 30th, 1st of October -> don't display because next month).
You can get the day, month very easy (see the link) to display it. The rest is up to you. Have fun!