Mount the downloaded ISO image on your target server. Run Setup.exe: Run the setup file as an administrator.
Yes – supported upgrade paths are Exchange 2013 CU21 or higher to Exchange 2016. But you cannot directly upgrade from 2010 or 2007; you need a migration. --- Microsoft Exchange Server 2016 Iso Download
: If you need older supported versions (typically the last two versions), they are listed on the Exchange Server Build Numbers and Release Dates : The ISO functions as an evaluation version Mount the downloaded ISO image on your target server