How to make 2 different cells act as one.

Hello all. I have been trying to figure out how to make two different cells act as one cell. I understand I can make the function =A1 and if I update A1 the cell with the function updates as well, but is there a way to make two different cells such as A1 and C3 act as the same cell? For example, if i update a value in A1 it updates in C3, but if I update C3 it will also update A1? I am specifically using this across two different sheets in the same workbook and two different tables. I appreciate the help and look forward to hear your replies.