GET method with query params

Hello I need to build a simple currency exchange rates app. I have node server that generates currency pairs and expose them with one endpoint, and second method with endpoint that generates rates that are updated every 10 seconds. I need to get those rates on the client side but simple get request is not working because on the server side is if check with array assigned to req.query in my server get route.

const { currencyPairIds = [] } = req.query;

that should send the ids of the currencies from the client.
I have those ids on the client but i don’t know how to send them to the server through req.query