Thanks for watching!
Here is the formula used in the video
=INDIRECT(D6&"!"&D6&"Total")
This shortcut works when the sheet names have the same name as the values you want to display (i.e. the sales for January and the sheet name itself is January)
Here is the note from the video that breaks down step by step how the formula works
Formula Example for January
=INDIRECT(D6&"!"&D6&"Total")
=January&!&January&Total
=January!JanuaryTotal
Returns cell B33 on January Tab
*If we hadn't named Cell B33 JanuaryTotal, we would have done =Indirect(D6&"!B33")
I hope this helps!