Scripting

you have three major option to install software:
1. (the best for 99.9% of the software) Distribution|Managed Install if you only have one EXE file or MSI
    Just fill out all fields for your MSI or EXE file and use the silent parameters. I suggest to use "overwrite default" and write the full commandline: msiexec /i software.msi /qn (if the msi you have is named software.msi) 
For exe-files you need to use this option anyways. But depending on the packaging the silent parameters can be different. Contact the software vendor for help here.
For a detailed how to, see here: https://support.quest.com/technical-documents/kace-systems-management-appliance/10.2%20common%20documents/administrator-guide/149#TOPIC-1407989

2. (if you need additional parameters, files etc) Create a script under Scripting. You can also use the Scripting| Configuration Policies| Windows MSI installer to do so
https://support.quest.com/technical-documents/kace-systems-management-appliance/10.2%20common%20documents/administrator-guide/154#TOPIC-1408006

3. (if it is "Stickware" or does not need to be installed but just unzipped) Create a File Sync under Distribution | File Synchronization 
https://support.quest.com/technical-documents/kace-systems-management-appliance/10.2%20common%20documents/administrator-guide/151#TOPIC-1407997

The ability for the install to be silent depends on the software vendor to provide this capability in the installer options.