Hello Deepak john
These is sensitive question which lots of animators has been seeking answer too
Maybe these steps below will help you out
1. Create an inclusion or exclusion list of your cameras in the Object Properties panel.
2. Create a user data field of type “Real” or “Integer” to use as your index.
3. Create an Xpresso tag on your object and link the user data index to a Range Mapper node to map the index value to the range of cameras in your list.
4. Link the output of the Range Mapper node to the input of a Camera Switcher node.
5. Use the Camera Switcher node to switch between the cameras based on the index value.
However, you can try searching for “Cinema 4D camera switching with user data” or a similar query on YouTube to find relevant tutorials or videos.
THANKS