Advice re casting streaming app with subtitles to Chromecast would be most welcome!

[Entotre 0]

I am a rookie to the world of VPN'ing.  And certainly not technical!  However, I have got as far as using Air VPN and am now able to bypass my country's restrictions.... to an extent.

What I am having a problem with is that when using a streaming app with Air VPN, I can watch the content with subtitles on my android device.

BUT ... I cannot cast the content with or without subtitles to the Chromecast.   Of course, the Chromecast is still set as being in my country and I have NO idea how to get around that.

I am reading and researching the problem but just wondered if there is a kind person in these forums who have an immediate answer to solve my problem?

Edited ... by Entotre
I got a fact wrong!