I have brother mfc-7340 all in one equipment, I want to scan file on network share

In that Brother model line, model MFC-7345N supports direct network scanning. Model MFC-7340 does not.

A possible workaround is to connect the MFC to a networked machine, use that machine to scan, and then copy the resulting file to a network share. However, the more users there are, the more hassle this becomes. Upgrading the machine to another model that can be directly networked may be a better solution.

MFC-7340 User's Guide
MFC-7340 Software User's Guide