Is my static-site/server application flow feasible or possible?

Hey all,

I am in a bit of a predicament because my company is using a Static-Site and would also like to use Universal Login and also use a primitive form of an express API for the backend.

when navigating to the login endpoint, entering the proper credentials, then navigating to @me endpoint I am able to receive the relevant information.

However, once I use my static site with a link to the login endpoint and then attempt to query the @me endpoint I receive an unauthenticated error. I understand that this is most likely an issue with cross-origin authentication but is this even the best way to go about using our tech stack?

If not, is there a better way to handle this?
If so, what might I be doing incorrectly?