Reference Link: 

http://blog.robseder.com/2014/02/20/more-on-wix-and-suppressing-the-license-dialog/

Customize wix UI: Only keep Welcome & Browsing install directory dialog

Add following code snippet somewhere between <Product> and </Product>.

    <UI>      <Property Id="WIXUI_INSTALLDIR" Value="INSTALLFOLDER" />      <UIRef Id="WixUI_InstallDir"/>      <UIRef Id="WixUI_ErrorProgressText" />      <Publish Dialog="WelcomeDlg" Control="Next" Event="NewDialog" Value="InstallDirDlg" Order="2">1</Publish>      <Publish Dialog="InstallDirDlg" Control="Back" Event="NewDialog" Value="WelcomeDlg" Order="2">1</Publish>    </UI>

Please note that, if you don‘t specify Order property, UI will go back to LicenseDlg when you click Back button on InstallDirDlg.

Source code of WixUI_InstallDir:

http://wix.cvs.sourceforge.net/viewvc/wix/wix/src/ext/UIExtension/wixlib/WixUI_InstallDir.wxs

Source code of WixUI_Minimal:

http://wix.cvs.sourceforge.net/viewvc/wix/wix/src/ext/UIExtension/wixlib/WixUI_Minimal.wxs

Wix installer: suppressing the License Dialog