You can run it locally on your machine, without a license it will only run 4 hours, and is limited to 5 users.
Sandbox is free, no limit in the users, but has limited resource. https://docs.mendix.com/developerportal/deploy/mendix-cloud-deploy
You could run it on you own server https://docs.mendix.com/developerportal/deploy/on-premises-design This requires a license.
You could build mobile offline app https://docs.mendix.com/refguide/offline-first though it requires a backend for syncing data.
Your HTML is part of the deployment package. https://docs.mendix.com/refguide/create-deployment-package-dialog#1-introduction but you can run it standalone it always requires a server.