Start with the right checks.
A flashing question mark means the Mac cannot find an available, working startup system. It is not a request to create a new Apple Account.
What to do next.
Take a photo of the symbol and note whether it appears briefly or prevents startup completely.
If an external startup drive is normally used, check its power and connection without changing its contents.
Use Apple’s instructions for this exact symptom and model. A brief warning followed by normal startup differs from a Mac that cannot start.
Before repair or reinstall work, establish the state of your backup and whether important files exist only on this disk.
Check the result.
If the Mac starts, open important files and make a checked recovery copy. Recurring startup warnings still need investigation.
Stop and get help if…
Disk Utility cannot see the disk, repair reports a failure or the proposed next step is an erase. Get the effect on your files explained before continuing.