How to make it so that when the button is clicked, the seconds taken from the URL (sec variable) start counting and the timer is displayed on the button?

Question

React

return (
            <Container className="mt-5" style={{width: '400px'}}>
                <h1 className = "text-center mb-2">Example Form</h1>
                <Form>
                    <div className="panel panel-default text-center">
                        <FormErrors formErrors={this.state.formErrors} />
                    </div>
                    <Form.Group>
                        <input
                            placeholder="Enter number"
                            type="number" className="form-control" name="sec"
                            value={this.state.sec}
                            onChange={this.handleUserInput} 
                        />
                    </Form.Group>

                    <Button id="sendNumber" className="btn btn-primary btn-block" type="submit" disabled={!this.state.formValid}>Send nubmer</Button>
                </Form>
            </Container>
        );