Select sheet (click triangle immediately to the left of ColumnA and immediatley above Row1), Home > Styles - Conditional Formatting, New Rule, Format only cells that contain, Cell Value equal to =$AL$1
, Format, Fill, Red, OK, OK.
Edit following clarification of requirement:
Change to Use a formula to determine which cells to format and apply
=SUBSTITUTE(CELL("address",A1),"$","")=$AL$1
Edit to add image of part of file uploaded by OP and some CF clarification.

Edit OP has an answer that works but posted this as a link in a comment. There is a solution that does not require formulae in AH1:AJ4
now that AA3
contains =TODAY()
:
=OR(AND($C5=TEXT($AA$3,"mmmm"),C8=DAY($AA$3)),AND($C4=TEXT($AA$3,"mmmm"),C7=DAY($AA$3)))
in Format values where this formula is true: and Applies to =$C$7:$AG$125
. (Now formats both day of week and date of month).
Edit. Attempt at clarification (that should have been provided before!)
Selecting C7
as the start point, the formula for conditional formatting checks whether A or B is true:
A] Both the month name (in C5) matches the current month (long form) of =TODAY() in AA3) and the cell immediately below (ie C8) matches the day in AA3,
Or
B] Both the month name (in C4 – that is merged with C5) matches the month and the current cell (C8) matches the day in AA3.
Either case triggers the conditional formatting – hence this is applied in pairs of vertically adjacent cells.
Since the spreadsheet is well laid out (each month 11 rows and Day1 always in ColumnC) this same formula can be applied throughout with the nature of conditional formatting taking care of adjusting the relative references to cells in ColumnC up to the specified limit of Row 125 and in Row7 (or 8) for columns up to the specified limit of AG.