This is heart-breaking. The guy is talking to his mom and brother, mainly his brother.
He told his mum he's been captured and she's asking where, he answers Ukraine. I think she asks why he's there and he said they just told us in the morning to go. She's also asking where he is in Ukraine and he says he doesn't know. Finally, the Ukrainians are urging his relatives to call his commander/the army and ask them to stop the invasion.
Not a perfect translation but the gist is that this is the best 'propaganda' for Ukraine, directly trying to expose Putin's willingness to throw his people to the wolves.