You may use the following commands to install the Microsoft Exchange Server 2016 Mailbox Server role from the command line.

Setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms
Setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms /OrganizaionName:
“<Organization Name>”
Setup.exe /mode:install /role:Mailbox /IAcceptExchangeServerLicenseTerms