Several approaches to convert Thunderbird to Outlook, like by manual method I which we have create a folder in Thunderbird and a backup in EML format, which then is imported t outlook. This method can result in data loss and requires a great knowledge to perform making it a difficult apporch to follow.

On the other hand, using professional tools like BitRecovery Thunderbird Converter Wizard can be a great option, which allows you to choose your data format, destination, and is simple to use. To perform, download and open the software, then add your credentials, choose your desired destination, and format like PST, MBOX, PDF, etc., then click on export, the data will be exported, then import it in outlook client to complete the task.