Hello @Omar Ahmed
To achieve what you are asking for, you can use Azure Object Anchors, which is a managed cloud service that converts 3D assets into AI models that enable object-aware mixed reality experiences for the Hololens.
You can follow the steps in the Unity HoloLens with MRTK quickstart to create a Unity HoloLens app that uses Azure Object Anchors. Once you have created the app, you can use the Hololens 2 to scan the car and upload the 3D model to Azure Object Anchors.
You can then stream the 3D model to your colleague and update it from your Hololens as needed.
To add annotations and drawings, you can use Unity to create a UI that allows you to add and edit annotations and drawings on the 3D model.
I hope this helps!