Hello,
The best way to start preparing your migration is to look at Cloud Adoption Framework (https://aka.ms/caf).
Before starting the migration, there are many things that your organization needs to figure out. For example, you will need to look at:
- ensure that you have a budget for your project
- evaluate your existing environment, and find out if the migration is possible
- prepare a migration plan for all your servers and applications
- evaluate team skills and readiness
- prepare landing zone that will include subscriptions, network, and connectivity to on-premises
- implement azure governance
- migrate servers, services, networking
- post-migration steps such as optimization, security, compliance,...
Also, handling medical information might require additional layers of security or compliance, depending on your location. In the USA, this is regulated by HIPAA.
There are many things to think about, but Cloud Adoption Framework should help you answer many of these questions.
Let me know if this is a sufficient answer to your question or if you need more information.
Vukasin