Email works perfectly at home. On the road using hotel wifi we receive mail but can not send. Help

It probably has something to do with the hotel's wi-fi setup and your mail provider will not allow what is called relaying. Can you send mail when on cellular data outside of home? Many years ago, Comcast mail was like that and you could not access mail when not on their network. I suggest contacting your email provider and ask them about sending mail from another network. It may be a security (SSL) issue.

This would be expected behaviour if you are using an email account provided by your internet provider. If this is the case, try using the webmail option to allow you to send and receive messages.