1. For fundamental first steps in the Arduino universe (LED blink, Button Read, Read ADC, Serial Print) get Arduino UNOs and electronic parts such as breadboard, LEDs, 220 Ohms resistors (or larger, to protect the LEDs), potentiometer, push buttons, etc., asap.
2. If not possible, use the Heltec CubeCell boards which are programmable in the Arduino IDE, too.
3. Install the Arduino IDE together with the CubeCell tool chain on your computer. You can download it from here.

Install the CubeCell Arduino Toolchain from here:
https://heltec-automation-docs.readthedocs.io/en/latest/cubecell/quick_start.html

• https://docs.arduino.cc/learn/starting-guide/getting-started-arduino