Anyone here with experience creating intake forms for patients (PII data) and pushing it over to a CRM or other DB?

Anyone here with experience creating intake forms for patients (PII data) and pushing it over to a CRM or other DB?

My concern is about the security and if it is safe to push the data through an API and into a CRM or some other database. Is there a recommended database to house PII sensitive data? Are there security measures to take? My understanding is that the API's all have the OAuth and that should be enough to ensure that the data while being transferred is encrypted.