You must remember that Roku is not officially supported world-wide, and in unsupported countries it is hit or miss (usually miss) if content is available there. To see what countries are supported by Roku, go to the main Roku web site and scroll to the very bottom. There's a link you can click that shows the country you are viewing on their site, and if you click (change) a box will open showing all supported countries.
Now, just because a country is not listed there, it doesn't mean a Roku can't be used. Some channels, such as YouTube, are available world-wide. But channels like HBO Max, Disney+, and many of the other popular channels, won't work, or simply aren't even available to install. Roku doesn't control that, the providers do.
If there's a specific provider you'd like to have available on your Roku, you need to contact that provider. Roku does not create and maintain channels for other providers. Only the content provider can create a channel for Roku devices and permit it in the location you desire.
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