Does anyone know how to code following condition for linking?

There are 2 spreadsheets TTT and PPP:
I would like to link a cell A1 under report sheet for TTT spreadsheet from
a cell A1 under 6183 sheet for PPP spreadsheet, but the code of 6183 is
given in a cell B1 under report sheet for TTT spreadsheet.

Under report sheet for TTT spreadsheet,
I would like to use indirect function to join 6183 from B1 under report
sheet for TTT spreadsheet in order to form the link for A1.
Does anyone know how to code it?
Thank you in advance
Eric