Open the MBOX file using an email client that supports MBOX files. Some examples of email clients that support MBOX files include Thunderbird, Apple Mail, and Microsoft Outlook.
Once you have opened the MBOX file in your email client, locate the email that contains the attachment you want to extract.
Right-click on the email and select "Save As" or "Save Attachments" from the context menu. This will allow you to save the attachment to your computer.
If your email client does not have a built-in option to save attachments, you can also use an MBOX to EML converter tool. This tool can convert individual emails in the MBOX file to EML format, which can then be opened in an email client that supports EML files. Once you have opened the email containing the attachment in an EML-compatible email client, you can save the attachment using the method described in Step 3.
Repeat steps 2-4 for each attachment you want to extract from the MBOX file.
Once you have extracted all the attachments you want, you can close the MBOX file in your email client or delete it from your computer.