Generating Calendars--In Whole or in Part
We frequently see requests that require generating all or part of a calendar. The rococo nature of the Gregorian Calendar makes this non-trivial, so here's a fairly simple way to get what you need from Excel.
The specifics of any particular problem generally require generating weekdays from a particular date, often spanning month and year boundaries. For this illustration, I'll simply generate a calendar for a whole year. It should be clear how to modify it as needed.
This formula generates the calendar for 2026. There are no month or year labels, but it should be clear (from inspection) that the data are correct:
=LET(ss, DATE(2026, SEQUENCE(12), 1), dd, ss-WEEKDAY(ss)+SEQUENCE(,42), cells, IF(MONTH(dd)=MONTH(ss),DAY(dd),""), WRAPROWS(TOCOL(cells),7) ) 
So how does this work? The key idea is to think of each calendar month as having 6 weeks, albeit with some blank cells. For example, August 2026 starts on a Saturday and ends on a Monday, so it needs six blank cells in the first row before the first and it needs five blank cells in the last row after the 31st.
ss is a column vector of the dates of the first of the month for all 12 months in the calendar for 2026.
dd turns this into a table of dates for 12 42-day months. These are full Excel dates--not just days of the month. Each row is a single month. So for August, the first day in dd is July 26 and the last one is September 5.
cells rather elegantly converts dd into days of the month and turns the excess dates into spaces. This is the data structure that's probably the most useful.
Nevertheless, I couldn't resist showing how WRAPROWS turns this into the form of a calendar we're most used to.
Obviously if you want it formatted with names of months and days of the week, it'll require a good bit more code, but what I most wanted to show was how to get to the cells array, since I think that's the key jumping off point.
I do have code that makes a (relatively) pretty calendar, if anyone actually wants to see it. :-)
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