Hi Hugo.

Yes, you can use tinyGSM library.

You just need to ensure that you have the right pin assignment on the code. For example, in our case, the board uses the following pins:

#define MODEM_RST 5
#define MODEM_PWKEY 4
#define MODEM_POWER_ON 23
#define MODEM_TX 27
#define MODEM_RX 26
#define I2C_SDA 21
#define I2C_SCL 22

You can use any other pins to connect your SIM800L module, but you need to set them right on the code in the previous snippet.
I hope this is clear.

ESP32 SIM800L Projects:

• ESP32 SIM800L: Send Text Messages (SMS Alert) with Sensor Readings
• ESP32 Publish Data to Cloud without Wi-Fi (TTGO T-Call ESP32 SIM800L)

Overview of the T-Call ESP32 with SIM800L GSM/GPRS board.

I hope this helps.

Regards,

Sara

Thankyou for your answer.
Why should I use 

#define I2C_SDA 21
#define I2C_SCL 22

Single module SIM800l only Has 
GND,TX,RX,RESET,Vcc.

Thanks in advance.

Hi Hugo.
The T-Cal ESP32 with SIM800L has a battery connector and an IC for power management. 
That IC is connected to the SDA and SCL pins. I think if you’re using a separated module, you don’t need that.
Regards,
Sara