Adding non-Ring Central fax numbers and text numbers to contacts in Ring Central App.

We would like to use the Ring Central Desktop app to one-click fax or text non-Ring Central numbers. It's not reasonable to ask all the doctors' offices we fax, and doctors we text, to provide an email address and ask them to take time to download and setup a Ring Central app. They just won't do it. It seems reasonable that if I can type in a random phone number to send a text, that I would be able to save that number in a list of contacts. Maybe there is a way to access our "personal" contacts from ringcentral.com? We use the Standard plan. Thank you.