Go to Icomoon.com, select a font pack and add. For example, I would like to use some icons from this the set Entypo+.
Click add and select the icons you want to use on your Webflow site.
Next, click Generate Font and Download.
Upload the font in Webflow. Use the .woff file.
Open the demo.html and copy the desired icon (it’s a block on the demo site, but don’t worry.)
Open the designer. Mak a text block, paste in the icon and select the font Icomoon. Done!