JAVASCRIPT

use onchange with react select

const [valueState,setValueState] = useState("")
// create a function that handle the React-select event and
// save the value of that event on an state every time the component change
    const handler = (event) => {
        const value = event.value
        setValueState(value)
    }
<Select options={"your options"} onChange={handler}/>

select in react with nchange

import React from 'react';
import Select from 'react-select';

const options = [
  { value: 'chocolate', label: 'Chocolate' },
  { value: 'strawberry', label: 'Strawberry' },
  { value: 'vanilla', label: 'Vanilla' },
];

class App extends React.Component {
  state = {
    selectedOption: null,
  };
  handleChange = selectedOption => {
    this.setState({ selectedOption });
    console.log(`Option selected:`, selectedOption);
  };
  render() {
    const { selectedOption } = this.state;

    return (
      <Select
        value={selectedOption}
        onChange={this.handleChange}
        options={options}
      />
    );
  }
}