As many have stated ISO 14971 is the major ISO regulation governing Risk Management.I agree with @thuytienleco that the major phases include: risk analysis, risk evaluation, risk control, residual risk evaluation, risk/benefit analysis, evaluation of overall residual risk acceptability, risk management report, production& post-production. I also found an article that goes into 5 tips in managing Risk Management:

1. Get a copy of the latest version of ISO 14971
2. Establish a Risk Management Policy and Procedure for your Company
3. Keep the severity, probability, and risk levels simple
4. Use risk management as a tool during design & development
5. Use risk management as a tool after design & development

I think #3 is a helpful hint to keep it simple and use 3 – 5 levels for severity and probability. As Dr. Simon mentioned in lecture, its important to use risk management as a tool during the design and development. For example, you should think of the potential hazards and hazardous situations and this assessment should be considered and influence the design inputs and this will also come into play for design outputs, verification/validation. I also think its important to stress the importance that the risk management document should be used/treated as a living document. So even when the development process is completed it should still be used as a tool after design and development. So you can keep a living document of production and post-production occurrences including CAPAs, complaints, etc.

https://blog.greenlight.guru/introduction-to-medical-device-risk-management