I like to retrieve data from two Lists. The main list is called OIE ALerts. The secondary List is Countries. I like to get the country code for the Country field in OIE Alerts. The country code is the second list.
OIE Alerts, field Country (lookup) = "Nederland" Countries, field LandNaam (single line) = "Nederland", LandCode (single line) = NLD
Found this example but confused how to make it work for me:
var urlForOrderBy = "/_api/Web/Lists/GetByTitle('OIE Alerts')/Items?" + "$select=ID,Title,Country,Date_of_Event,LandCode," + "SpPerson/Name,SpPerson/Title,SpLookup/Title,SpLookup/ID" + "&$expand=SpLookup,SpPerson&$orderby=Date_of_Event desc";