Is there a possibility of interference between the first online website and the second project if I publish the second project with only the option to deploy on the staging URL in Webflow?

No, there should not be any interference between the first online website and the second project if you choose to publish the second project with only the option to deploy on the staging URL in Webflow.

When you publish a website in Webflow, each project has its own unique URL, whether it's the live domain or the staging URL. Each project operates independently and is hosted on separate server infrastructure.

By default, when you publish a project in Webflow, it deploys to a unique URL on the staging subdomain (e.g., project-name.webflow.io). This allows you to preview and test your changes before pushing them to the live domain. The staging URL is separate from the live domain and does not affect the existing website or other projects you have in Webflow.

So, if you choose to only deploy the second project to the staging URL, it will not interfere with the first online website at all. The first website will continue to function as it did before, and the second project will be accessible only through its staging URL.

However, it's important to note that the staging URL is not meant for permanent production use. It's primarily intended for testing and previewing purposes. If you want to make the second project live and accessible to the public, you should consider configuring a custom domain for it or publishing it to the live domain instead.

By separating your projects using different URLs, you can ensure that they function independently without any interference between them.