How to copy the value of a cell from a different tab, using the string of a cell as name of the tab in Excel?

I would appreciate your help in creating a function that can copy the value of a cell from a different tab, using the string contained in a cell to understand which specific tab.

I have two columns, A and B.A contains the list of all the tabs I have in the excel file:

A1 = "XXX";  A2 = "YYY";  A3 = "ZZZ";  etc.. 

I need a function to fill in values of B column:

• B1 should contain the value that is in cell A101 of the "XXX";
• B2 should contain the value that is in cell A101 of the "YYY";
• B3 should contain the value that is in cell A101 of the "ZZZ";
• etc...

I'm not sure how to do it rather than manually clicking on the cell A101 of the specific tab.