Hi @Nafisa Zaman,
Check the below link for ServiceNow icons available (using the icon name):
https://hi.service-now.com/styles/heisenberg/styleguide/docs/guidelines_-_icons.html
You can also use (or add) any instance specific images stored on your instance by typing 'Images' into the Navigation menu.
Additionally, for the Next Experience and workspaces, see the below link for the available gallery.
https://developer.servicenow.com/dev.do#!/reference/next-experience/orlando/now-components/now-icon/...
To help others (or for me to help you more directly), please mark this response correct by clicking on Accept as Solution and/or Kudos.


Thanks, Robbie
