Welcome to the community!
Your current mobile plan is linked to your phone number and may not be available in other Provinces. Even if the plans appear identical, there might be cost differences between the Provinces. If you would like to change your phone number between Provinces, you'll likely also need to change your plan to one available in your new Province.
If you would like to change your phone number and plan, you will likely need to contact customer service so they can access your account to perform the change. I don't think My Account will allow both changes at the same time. Alternatively, you might consider sending @FidoSolutions a PM. Once they verify some information, they'll also be able to access your account.
If you wish to keep your current plan, you would need to keep your Manitoba phone number as well. You should note that the taxes on your bill are also related to your phone number, not where you reside. Since most plans now include Canada-wide calling, keeping your phone number from a different Province would not incur long-distance charges. However, you should also note that for people from Ontario calling your phone number, their calls would be considered long-distance, even though you might be in Ontario.
Hope this helps 😀