What happens to incoming texts and calls when outside of US, Canada, or Mexico?

[matterfact]

What happens to incoming texts and calls to a visible number when outside of the US, Canada, or Mexico?

If someone sends a text from the US to my visible number while I am in S.E. Asia, will I receive the text when connected to wi-fi? If I am not near wifi, will the sender get rejected and I wouldn't receive the text? Or would the text be received when I get back to a wi-fi connection?

If someone calls from the US to my visible number while I am in S.E. Asia, will I receive the call if connected to wi-fi? If I am not near wifi, can the caller leave a voicemail or will the caller get rejected?  

[GreenSub]

Apple iMessage texts should go through when overseas and connected to WiFi

Traditional cellular texts and calls should go through if you are connected to WiFi AND have activated and tested WiFi calling on the Visible network while in the United States.

You might want a free Google Voice account as a backup.