io.netty.channel.ConnectTimeoutException: Connection timed out:

So I am playing on a Microsoft server and want to join a aternos server of my friend . my brother is playing on a different account I the same house on that server because we play together and has no issues going on it but here I am texting you after freshly giving you 23 bucks of my money not being able to enter that stupid server because of the above written exception or timeout. I am on a Mac and don't know what to do anymore. I don't have a firewall idk what in the world I could do differently anymore to get on that server . all I want is to play a little thank you that's all I have to say I really hope to get a message or someone who can fix this bug because idk anymore. 

I need help thank you