Hi Joy Abaja,
I go through the post carefully, there could be no out-of-box settings to restrict permission on column level in SharePoint Online. However, based on my research, you may find a possible solution using Microsoft Power Auto Mate, check the links for more information:
Manage list item and file permissions with Power Automate | Microsoft Docs
Set Item Level Permission in SharePoint List using Power Automate | Netwoven
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If you need helping on building flows in Power Automate, please post in Microsoft Power Automate Community - Power Platform Community where you may get dedicated help.
Best Regards,
Clark