Adding GitHub Library to PlatformIO

I tried to add this GitHub Library (LilyGO-T-A76XX) to my PlatformIO using the HTTPS link.
This is my .ini file:

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino

lib_deps =
    https://github.com/Xinyuan-LilyGO/LilyGO-T-A76XX.git

And then I tried to copy one of the example code of the Library which is (DeepSleep). This is my main.cpp code:

#include <Arduino.h>
#include "utilities.h"
#include <driver/gpio.h>

#define TINY_GSM_RX_BUFFER          1024 // Set RX buffer to 1Kb

// See all AT commands, if wanted
#define DUMP_AT_COMMANDS

#include <TinyGsmClient.h>

#define uS_TO_S_FACTOR      1000000ULL  /* Conversion factor for micro seconds to seconds */
#define TIME_TO_SLEEP       30          /* Time ESP32 will go to sleep (in seconds) */


#ifdef DUMP_AT_COMMANDS  // if enabled it requires the streamDebugger lib
#include <StreamDebugger.h>
StreamDebugger debugger(SerialAT, Serial);
TinyGsm modem(debugger);
#else
TinyGsm modem(SerialAT);
#endif

void setup()
{
    Serial.begin(115200); // Set console baud rate

    SerialAT.begin(115200, SERIAL_8N1, MODEM_RX_PIN, MODEM_TX_PIN);

    if (esp_sleep_get_wakeup_cause() == ESP_SLEEP_WAKEUP_TIMER) {
        Serial.println("Wakeup timer");
        int i = 30;
        while (i > 0) {
            Serial.printf("Modem will start in %d seconds\n", i);
            Serial.flush();
            delay(1000);
            i--;
        }
        Serial.println("TurnON Modem!");
    }

    // Turn on DC boost to power on the modem
#ifdef BOARD_POWERON_PIN
    pinMode(BOARD_POWERON_PIN, OUTPUT);
    digitalWrite(BOARD_POWERON_PIN, HIGH);
#endif

    delay(2000);
#ifdef MODEM_RESET_PIN
    // Release reset GPIO hold
    gpio_hold_dis((gpio_num_t)MODEM_RESET_PIN);

    // Set modem reset pin ,reset modem
    // The module will also be started during reset.
    Serial.println("Set Reset Pin.");
    pinMode(MODEM_RESET_PIN, OUTPUT);
    digitalWrite(MODEM_RESET_PIN, !MODEM_RESET_LEVEL); delay(100);
    digitalWrite(MODEM_RESET_PIN, MODEM_RESET_LEVEL); delay(2600);
    digitalWrite(MODEM_RESET_PIN, !MODEM_RESET_LEVEL);
#endif

    pinMode(MODEM_DTR_PIN, OUTPUT);
    digitalWrite(MODEM_DTR_PIN, LOW);

    Serial.println("Power on the modem PWRKEY.");
    pinMode(BOARD_PWRKEY_PIN, OUTPUT);
    digitalWrite(BOARD_PWRKEY_PIN, LOW);
    delay(100);
    digitalWrite(BOARD_PWRKEY_PIN, HIGH);
    //Ton >= 100 <= 500
    delay(300);
    digitalWrite(BOARD_PWRKEY_PIN, LOW);

    // Pull up DTR to put the modem into sleep
    pinMode(MODEM_DTR_PIN, OUTPUT);
    digitalWrite(MODEM_DTR_PIN, HIGH);

    // Delay sometime ...
    delay(10000);

    Serial.println("Check modem online .");
    while (!modem.testAT()) {
        Serial.print("."); delay(500);
    }
    Serial.println("Modem is online !");

    delay(5000);


    Serial.println("Enter modem power off!");

    if (modem.poweroff()) {
        Serial.println("Modem enter power off modem!");
    } else {
        Serial.println("modem power off failed!");
    }

    delay(5000);

    Serial.println("Check modem response .");
    while (modem.testAT()) {
        Serial.print("."); delay(500);
    }
    Serial.println("Modem is not respone ,modem has power off !");

    delay(5000);

#ifdef BOARD_POWERON_PIN
    // Turn on DC boost to power off the modem
    digitalWrite(BOARD_POWERON_PIN, LOW);
#endif

#ifdef MODEM_RESET_PIN
    // Keep it low during the sleep period. If the module uses GPIO5 as reset, 
    // there will be a pulse when waking up from sleep that will cause the module to start directly.
    // https://github.com/Xinyuan-LilyGO/LilyGO-T-A76XX/issues/85
    digitalWrite(MODEM_RESET_PIN, !MODEM_RESET_LEVEL);
    gpio_hold_en((gpio_num_t)MODEM_RESET_PIN);
    gpio_deep_sleep_hold_en();
#endif

    Serial.println("Enter esp32 goto deepsleep!");
    esp_sleep_enable_timer_wakeup(TIME_TO_SLEEP * uS_TO_S_FACTOR);
    delay(200);
    esp_deep_sleep_start();
    Serial.println("This will never be printed");
}

void loop()
{
}

However, I am getting this error:

src/main.cpp:2:10: fatal error: utilities.h: No such file or directory

*******************************************************************
* Looking for utilities.h dependency? Check our library registry!
*
* CLI  > platformio lib search "header:utilities.h"
* Web  > https://registry.platformio.org/search?q=header:utilities.h
*
*******************************************************************

 #include "utilities.h"
          ^~~~~~~~~~~~~
compilation terminated.
*** [.pio\build\esp32dev\src\main.cpp.o] Error 1

How do I make the build/compile successful? Thank you.

This repository is not a library but a project!

You have to clone the repo and configure the project by editing the platformio.ini.