A simple get request in react. What am i doing wrong - react-native

Question

IM doing a simple get Request. I want to put the response in my state array.
export default function App() {
state = { features: [] };
useEffect(() => {
fetch(featuresURL, oParam)
.then((response) => response.json())
.then((data) => {
this.setState({ features: data });
})
.catch(() => alert("Bad request"));
}, []);
what am i doing wrong ?
Im completely new to react. Im just learning
In fact what im trying to achieve is get markers on my react native maps.
this is my code:
export default function App() {
const [data, setData] = useState([]);
useEffect(() => {
fetch(featuresURL, oParam)
.then((response) => response.json())
.then((json) => setData(json))
.catch(() => alert("Bad request"));
}, []);
mapMarkers = () => {
return this.data.features.map((feature) => (
<Geojson
geojson={feature}
strokeColor="red"
fillColor="green"
strokeWidth={2}
/>
));
};
return (
<MapView
style={{ flex: 1 }}
mapType="mutedStandard"
initialRegion={{
latitude: 37.1,
longitude: -95.7,
latitudeDelta: 10,
longitudeDelta: 45,
}}
>
{this.mapMarkers()}
</MapView>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
},
map: {
width: "100%",
height: "100%",
},
});