You can just use one of the online ones, there's a plenty of them now. For example, Email Migration Service
https://convertemail.online/ is one of the most convinient in order to convert emails online, it's very easy in using and very safe in case of your data security because it doesn't belong to a third party software. It can be used for free too.There are many other online converters too and of course you can install some special programs on
your device too. But many of them are expensive and have high license fees.
