How do I check if a cell with a number equals to the day on a date on other cell?

Question

Basically, I'm doing a calendar with school assignments with dates.

I made a mini calendar on the left side (one day for each cell) and on the right side I have a list of assignments and the corresponding delivery dates.

I wanted to, each time I add a date to that list, the corresponding day on the mini calendar gets color-filled with Conditional Formatting. How do I do that?

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Answer 1

Please clear formatting from and select A6:G10, Format - Conditional formatting..., Custom formula is and:

=match(date(2018,3,A6),$I:$I,0) 

Select formatting of choice and Done .

I have assumed:

a) when days of the week cause numbers to 'head' for outside the range they will be wrapped back to the start of the range.

b) you will replace 2018 and 3 to the relevant year/month, preferably via cell references.

c) Your dates are true date indices.