1. Earlier after creating the experience fragments I just exposed those experience fragments as plain HTML from AEM.
Using the .plain. selector in the URL, you can access the plain HTML rendition as defined here -

Please refer this: https://experienceleague.adobe.com/docs/experience-manager-65/developing/extending-aem/experience-fragments.html?lang=en
2. Another application was making pull request to read the our experience fragments from AEM as html and get it displayed on their application.
3. We made necessary change at dispatcher level to allow experience fragments for that external application.
4. While accessing experience fragments from AEM we had encountered CORS issue and then we allowed that external application domain to prevent CORS issue.