Using CrmSvcutil.exe

Download CrmSdkCoreTools from

https://www.nuget.org/packages/Microsoft.CrmSdk.CoreTools (See the following link for download script to run from command prompt or powershell)

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/download-tools-nuget

Then, Open command prompt, navigate to tools directory and run the following command

CrmSvcUtil.exe ^
/url:[YourOrg]/XRMServices/2011/Organization.svc ^
/out:[Your]SdkTypes.cs ^
/username:[YourUsername] ^
/password:[Password] ^
/namespace:[Namespace] ^
/serviceContextName:[ContextName]