The goal of encryption is clear: To prevent unauthorized people from reading what they should not. Even if someone intercepts your messages or a cloud provider’s engineer opens your data stores, that encrypted data should be worthless without the key. Encrypted data must have a key (aka a cypher) to be unlocked.
Thus, protecting those keys — who has access to them — is the biggest challenge in safeguarding that data. Although your technology provider may offer tools to encrypt your data, you might need to do more to protect those keys and perhaps even bring your own.