Software Deployment

You could the information here: https://docs.microsoft.com/en-us/deployoffice/office2019/deploy#sample-configurationxml-file-to-use-with-the-office-deployment-tool

Using the line: RemoveMSI (In the Example shown below) will remove/uninstall Office 2016 and all older Microsoft application might also be installed on the PC such Project, Visio, etc. 

Example:

<Configuration>

  <Add SourcePath="\\Server\Share" OfficeClientEdition="64" Channel="PerpetualVL2019">

      <Product ID="ProPlus2019Volume"  PIDKEY="#####-#####-#####-#####-#####" >

         <Language ID="en-us" />

      </Product>

  </Add>

  <RemoveMSI />

  <Display Level="None" AcceptEULA="TRUE" />  

</Configuration>

1. Apply (official) Office nuke from here, some script skills required to put it all together.
   https://github.com/OfficeDev/Office-IT-Pro-Deployment-Scripts/tree/master/Office-ProPlus-Deployment/Remove-PreviousOfficeInstalls
   
2. Install Office like normal. There's are online guide everywhere, just grab one of them. In essence, you need a config xml to apply to the installer - to tell it what to install.

Recommend making them SCCM applications. You can set the Office nuke as a prereq for Office.

Have a look into PSDeploy Toolkit too, so you can give users some notice or defer the install. The read up and research into this will be circa 45 mins to get your head around it. You can use PSDeploy Toolkit as a wrapper around the Office Nuke and Office installer.

Alternatively, you can have this as a task sequence instead of a SCCM application too.