Let's say that you want to combine columns A to K, from row 2 down to the last used row in all sheets of Book1. And that column A will be populated in all used rows.
Make sure that both workbooks are open in Excel.
You can use a formula like this in A2 on the worksheet of Book2:
=VSTACK(
FILTER('[Book1.xlsx]Sheet1'!$A$2:$K$10000, '[Book1.xlsx]Sheet1'!$A$2:$A$10000<>"", ""),
FILTER('[Book1.xlsx]Sheet2'!$A$2:$K$10000, '[Book1.xlsx]Sheet2'!$A$2:$A$10000<>"", ""))
Change the name of the workbook and worksheets to the real names. Add more sheets as needed.
Close Book1. Excel will add the path of Book1 to the workbook name in the formula.
Save Book2.