Thank you @Mandisa for reaching out to us!
Yes, it is possible to do this and as @Agnes rightly suggested, you can use the Kiosk Lockdown feature. There are mainly two ways in which you can achieve this and for both, your iPhone needs to be supervised.
One of the methods is to enforce Single App Kiosk Lockdown in your device by choosing a browser app like Safari or Chrome. This will allow your employees to open any web page. At the same time, they won’t be getting access to any other apps like Phone, so outgoing calls won’t be possible. Here’s our detailed explanation on how to enforce Single App Kiosk Lockdown on iOS devices.
Also, you can configure Web App under the Kiosk Lockdown subtab. Enforcing a Web App kiosk prevents the users from accessing other apps. Here, either Safari or Hexnode Browser Lite can be selected. Choosing the latter gives you the added advantage of being able to configure a wide array of features via Advanced Website Kiosk Settings. Also, you can whitelist specific websites in Hexnode Browser Lite, thus enhancing the overall internet security.
Please refer to the documentation for a step-by-step procedure on how to enforce Web App Kiosk Lockdown.

Hope that helps. If you have any more queries, do reach out to us!
Cheers!
Gabriel Galbraith
Hexnode UEM