How do I fetch the current/active stage of an opportunity with OData API?

I am able to fetch an opportunity name and opportunityid by doing something like:

SELECT opportunityid, name FROM opportunity WHERE name LIKE '%search term%'.

However, now that I have the opoortunityid in the format '1d527eac-3f61-48cb-809a-12b0e7acb112', I would like to fetch the active stage of the opportunity in the Opportunity Sales Process.

If I also try to fetch stageid, salesstage in the query, they both return null. I also tried selecting

FROM opportunitysalesprocess WHERE opportunityid = '1d527eac-3f61-48cb-809a-12b0e7acb112'

but it returns: Resource not found for the segment "'opportunity sales process'".

How can I select the current/active stage of an opportunity by using the opportunityid?