You can manually enable .NET version 4.6.2 or later via Server Manager.
Steps to enable:
1. Open Server Manager and navigate to Manage > Add Roles and Features.
2. When the Add Roles and Features Wizard opens, click Next.
3. Select Role-based or feature-based installation and click Next.
4. Select your destination server and click Next.
5. On the Select server roles page, click Next.
6. On the Select features page, select .NET Framework > .NET Framework 4.x and click Next.
7. Confirm your installation selections and click Install.