To change organisation name

Hi Team,
In order to change organisation name or legal entity name we have few queries.
1. Do you need any legal supporting document as new organisation in order to name change?
2. What the throughput time to complete the process.
3. Can we change account owner name and email? if yes please let us know the process.
4. Please describe whole process so that we can prepare ourself in upfront.

We are looking forward to hearing from you soon.

Thanks,
Philips Lighting Team