Hi John,
Go to the 'Collaborate' page for your survey at survey123.arcgis.com - you'll find a link that can be given to people. If the survey was created via the Survey123 website, there will be a web link and a link to open in the field app (phone app). If you created the survey using Survey123 Connect, you'll find only the link to the field app. There is a new web form in Beta that can handle the more complex forms authored in Survey123 Connect. To access the beta web form, open the form in Survey123 Connect and click on the globe button; it has an option to 'Open in web app'. Click that, and the form will load in a browser.
On the field app links, we are finding some issues opening the form on Android devices; we've found the best experience is to create web page with a hyperlink. We will be implementing that in a future update of Survey123, though for now you would need to create the web page yourself.