You can make the creation of the formula easier, by typing = in the destination cell (in workbook B) and then clicking in the appropriate cell in workbook A and then pressing Enter/Return.
If you remove the $ characters from the formula, you can then copy the formula into all the other cells in workbook B where you need copies of data in workbook A.
Caveat: Based on years of experience, I don't recommend having formulae which reference other workbooks. There is too much scope for things to go badly wrong. My preference would be to have the data in two sheets in the same workbook.