HI Bailey. I'm Greg, 10 years awarded Windows MVP, here to help you.
OneDrive is designed so that you can access your files online by signing in with your Microsoft Account to www.Onedrive.com. You can then download the individual files or all of them to your replacement device.
Or you can set up OneDrive on the new PC and it will pull them down from the cloud following this guide:
https://www.windowscentral.com/how-get-started-...
If you had your Documents, Pictures and Desktop sync'd to OneDrive then the very latest copies of your files should be sync'd in OneDrive:
https://www.elevenforum.com/t/turn-on-or-off-on...
I would immediately change your Microsoft Account password so a thief will not be able to access your files any further:
https://www.tenforums.com/tutorials/14699-reset...
But from all I have seen a thief will quickly wipe the PC to reinstall Windows to destroy evidence of their theft, and if you had it passworded they would have a hard time getting in anyway.
I'm sorry you're going through this. Feel free to ask back any questions and I'll work with you until the transition is successfully competed as painlessly as possible.
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