Changing the password complexity requirements in Server 2019 is a straightforward process. Here are the steps to follow:
1. Open Server Manager and navigate to Local Users and Groups
2. Select Policies > Account Policies > Password Policy
3. Set your desired complexity requirements, such as minimum password length, password history, required characters etc., then click “Apply”
4. Close the window when done and restart the system for changes to take effect
It's important that you choose secure settings that meet your organization's security needs while still being easy enough for users to remember their passwords without having difficulty accessing their accounts.