EXCEL IF FUNCTION

Use the IF statement to put a star in each row where the students grade is equal to or higher than the class average in the Info Column; The star should be left-aligned within the column

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=IF(B4>=B17,"*")

I have used this formula but in a seperate column

I would need the * to appear in B4 for the formula above, how can I tell the * to appear in a cell that it is already pulling from?