Your patients definitely can!
Here's how to do it.
Step 1: Open the profile and open the call the screen
Step 2: Click the "Share Call Link" button
Clicking it will copy a link that you can share to your patient
Step 3: Send that Link to the Patient
You'll see that the link is already copied. So just send it to the patient via the messages area or via other channels like email or other chat apps.
Your patient will just need to load it on their browser like Google Chrome
Step 4: Press the Star Call Button
It's that easy!
Note that to secure this method, the system will generate a new call link each time you end the call and start a new call. So you will need to send the new call link to the patient again if you accidentally end the call.