For those who haven't done so, you'll want to download Telegra | This is backup (check description)

For those who haven't done so, you'll want to download Telegram app directly from the Telegram website if you have android. You can then delete the version from the play store.

If you see the message "This post/channel can't be displayed" this mean that google has censored it, not Telegram. Telegram does not practice censorship, but their application is hosted on the Google Play Store and AppStore, so they are dependent on Google/Apple censorship policies.

Once installed successfully from Telegram website directly all the posts/channels will be avaliable as usual. Google will give you warning it will harm your device. Lies. Proceed.

https://telegram.org/