If statement (circular references)

Hello, I believe my If Statement may need to be in a VBA. I've tried to figure out how VBA works for this specific situation, I'm completely lost.

I need the quantity in relation to the date in sheet 1 to update in sheet 2. So if the date changes the quantity for that specific date will change. The other dates remain untouched.

I was using formula =IF(Date=Date, Quantity, Quantity(Unchanged qty if false) which is =IF(B2='Sheet 1'!B$2,'Sheet 1'!B$2,C4)

Sheet 1
A B
1 Date: 1/21/2021
2 Quantity: 45

Sheet 2
A B
1 Date Qty
2 1/21/2021 45
3 2/21/2021
4 3/21/2021
5 4/21/2021
...

would a lookup work ?
can you post a sample sheet as indicated by the yellow banner
Also include you expected results in the sheet

you also have the thread SOLVED - so if its NOT solved, then you need to change the status - see my signature