Go

package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"os"
)

type Response struct {
	Data struct {
		Name      string `json:"name"`
		BirthDate string `json:"birthDate"`
		Gender    string `json:"gender"`
	} `json:"data"`
}

func main() {
	cpf    := "12345678909"
	apiKey := os.Getenv("CPFHUB_API_KEY")

	req, err := http.NewRequest("GET", "https://api.cpfhub.io/cpf/"+cpf, nil)
	if err != nil {
		panic(err)
	}
	req.Header.Set("x-api-key", apiKey)

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		panic(fmt.Sprintf("API error: %d", resp.StatusCode))
	}

	var result Response
	json.NewDecoder(resp.Body).Decode(&result)

	fmt.Println(result.Data.Name)      // "Fulano de Tal"
	fmt.Println(result.Data.BirthDate) // "15/06/1990"
	fmt.Println(result.Data.Gender)    // "M"
}