Hello! My name is Mostafa, and I’m an independent advisor and a long-time Microsoft user.
I'm sorry, but Microsoft discontinued support for Windows Phone in 2017, which means that new apps are no longer being developed for the platform. Furthermore, most app developers have also stopped providing updates and support for their existing apps on Windows phones. This makes it highly unlikely that you will be able to install new apps on your Nokia Lumia 800 in 2023. I would recommend considering a new smartphone.
In case of additional questions, reach out back to me, and I will be happy to help and try my best to resolve your issue. Thank you.
Best,
Mostafa
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