The corner of images can be rounded to your liking by changing the border radius.
To change the border radius, click on the image and go to the Image Attributes section > Border Radius. You can round the image up to 100px which will make the image appear as a circle.
The section and columns are similar to the image border radius being rounded. Go to the border area of the column or section and change the corner radius to a higher number to make the corners rounded.
Note: The Border Radius feature may not be supported in Microsoft Outlook.
Need more help? Contact support via live chat within Knak using the chat bubble in the bottom right corner or email email@example.com