Windows Install and Character Backup Questions

[Mirazh_Dragon 1]

Every so many years, I do a re-installation / version update of windows.

In this case, I'll be moving from 10 to 11. I do a reformat of the drive and install clean.

I scoured the web, forums and found nothing substantial addressing my inquiry succinctly.

Thus, my questions are the following,

Do the official servers or steam, contain my character data, hence there being no need for me to back anything up?

Just re-download everything from steam once my windows install is done?

Or, do I have to back up something on my PC to make certain I do not lose my character data?

Any insight on this would be greatly appreciated.

Thank you.

Mir

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