How to use the tab name from a cell in a formula in Spreadsheet?

Question

Google Sheets

There is a formula
=SUMIF('Table1'!A1:A;$A1;'Table1'!B1:B) The
question is how to write a formula so that the value of Table1 is substituted from the cell?
Something like:
=SUMIF('B1'!A1:A;$A1;'B1'!B1:B)

Answer 1

Form the cell address with CONCATENATE or & and feed it to the INDIRECT() function
=ДВССЫЛ("Лист1!"&"A1")