The title is incredibly hard to understand.

Thanks for the clarification I should have mentioned this. Especially for calls it is actually relevant but I feel like very few people actually use secret chats.

To clarify because this is always a point of confusion whenever the topic comes up. Telegram is, of course, transport encrypted. Someone listening on the wire cannot read your data. It is not end-to-end encrypted, meaning Telegram can always read your messages and can, in principle, give anyone access.

Blockchains have the property of being append-only, so a blockchain is precisely what makes it impossible to delete transactions. That being said, in a distributed system, once the message leaves trusted servers, it is obviously also impossible to delete it.

I think major training should just be done on dedicated servers/on the cloud. That being said it is very helpful to test locally, so in case you are planning on using Nvidia equipped servers just get any somewhat recent consumer Nvidia card and you can always run locally on some sample data and test much more easily.