Yes you can convert MBOX to PST manually but it takes lots of time. As it is the most common method but does not provide reliable results for Outlook. So if you still want to try then you can read it here: https://www.mailsdaddy.com/blogs/import-mbox-outlook-full-accuracy/
For the best result go with professional tools. MailsDaddy MBOX to PST Converter tool is the most effective and reliable tool to convert and import MBOX file to Outlook, O365, EML, Live Exchange etc.