4.5.x is an "in-place upgrade" to .Net 4.0, and 4.6.x is an "in-place" upgrade to 4.5.x so yes, 4.6.x should cover everything you need.
See here for details: https://msdn.microsoft.com/en-us/library/bb822049(v=vs.110).aspx
Targeting and Running .NET Framework apps for version 4.5 and later
The .NET Framework 4.5 is an in-place update that replaces ...
Go to Update History -> Uninstall Update and then ...
Client Win 10: Uninstall Update KB4486153
Windows server 2016: Uninstall Update KB4486129
Being a part of the Feature Update 1903, .NET 4.8 cannot be deinstalled except by a rollback to 1809 via control panel (Updates ->Recovery)
Requirements: Backup of 1809 is ...
The CLR.dll version number does not correspond to the .NET framework version number. .NET 4.0 through 4.5.2 will all report 4.0.x for the clr.dll version number.
You likely have the correct version installed already. If you really want to be sure, follow this MSDN article "How to: Determine Which .NET Framework Versions Are Installed"