how do i fix a white screen with a crossed circle

Prohibitory sign says, I FOUND MacOS, but when it was part way loaded, something was found to have too much damage to proceed.

What to do when your Mac shows only a gray screen or a Prohibitory sign (no left turn) at Startup:

1) First, use Disk Utility to Repair/First Aid your drive.

Since your Mac is not working normally, you can invoke Recovery Mode by holding Command-R at Startup.

Recovery Mode contains several useful functions, including a special version of Disk Utility that does not need the rest of MacOS to be running to do its job of repairing your disk.

"Regular" Recovery gets the Utilities from special partition on your normal boot drive. If you see a spinning globe, you have invoked (or fallen back to) Internet Recovery, and you see the Globe because it is fetching the Utilities from the Internet. This takes a little longer, so be patient.

About macOS Recovery - Apple Support

Once you get Disk Utility running, this article describes how to repair your disk:

Repair a disk using Disk Utility on Mac - Apple Support

Once Disk Utility reports your drive has been successfully repaired, you can try booting MacOS in the regular way. If that works, you have fixed the problems and you are done.

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If Disk Utility made some repairs, but there are still some problems remaining, you should run it again until your drive comes clean, or Disk Utility reports it cannot be repaired.

If disk Utility suggests you should ERASE your drive, that is a radical step -- this will delete all your files with no possible way of recovering them. Post back here for additional options before you do that.

2) Second re-Install-in-place.

Your MacOS is likely damaged. It is very difficult to repair the individual pieces, so it will need to be re-installed. You can only Re-install onto drive that is working correctly. If Disk Utility was not able to fix all the problems on your drive, there is no point in attempting a re-Install. the drive must be fixed first.

By design, a Re-install-in-place does not bulk-erase anything outside of System directories. Your added Applications, Preferences, and User Files are not modified.

You can do this directly from Recovery mode. The software for the Installation will be downloaded from the Internet. This may take an hour or more. Then it will need to be installed, which may take an hour or more.

How to reinstall macOS - Apple Support

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Which model?

If it's capable of running Internet Recovery, that would be the first thing I'd suggest.

About macOS Recovery - Apple Support

Run Disk Utility (start First Aid) to see if your disk and volume are corrupted. You might need to select View>Show All Devices for everything to be displayed.

Safe Mode requires MacOS to be intact and functioning normally.

Recovery mode requires only the recovery partition, a minimal partition that supports Utilities and Installer. Recovery does not require Safe Mode.

The model number you mentioned could refer to any one of 12 different 13-in MacBook pro shipped any time between 2008 through 2012, which can run many different version of MacOS. That is not nearly specific enough.

If your MacBook Pro is from after 2011, it may also have Internet Recovery in its ROM.