How are you receiving the street address? If it's coming from a reverse geocode, you should be able to request the specific subcomponent (see the 'AddNum' value in the sample at Geopoints—Survey123 for ArcGIS | ArcGIS ). If you are trying to parse text entered in a form question, that could be more difficult.
I see there is a something for getting the address numbers but there isn't anything for the street. I figured I would need to somehow remove the everything before the first space which would remove the house number.
It may help to see the response first - street name may be in the response. The World Geocoding Service documentation (geocodeAddresses—ArcGIS REST API: World Geocoding Service | ArcGIS for Developers ) shows it in the response.