Windows server 2016 , unable to install .net framework

I accidentally removed .net framework 4.5 feature from server manager in windows server 2016 machine.
Now I’m not able to open any windows component (server manager , IIS , Powershell …) where I’m getting this error :

To run this application,you first must install one of the following
versions of the NET Framework: v4.0.30319 Contact your application
publisher for instructions about obtaining the appropriate version of
the .NET Framework.

I tried to install .NET Framework 4.7.1 , the installation finishes successfully , but when I reboot my computer , it turns up that the .net framework is not installed.

When I try to install v4 I get :

Microsoft .NET Framework 4 is already a part of this operating system,
but it is currently turned off. To enable the .NET Framework 4 , use
Turn Windows features on or off in Control Panel.

But unfortunately I’m not able to access server manager to install the feature.

any help would be appreciated