The easiest way is to follow the Raspbian software installation guide at https://www.raspberrypi.org/learning/software-guide/quickstart, which is, in summary, a simple three-step process:
- Download and install the SD Formatter (https://www.sdcard.org/downloads/formatter_4/index.html) for your Windows or Mac.
- Use the SD Formatter to format a MicroSD card.
- Download the offline ZIP version of New Out Of Box Software (NOOBS), the official easy installer for Raspbian, at https://www.raspberrypi.org/downloads/noobs, unzip it, and then drag and drop all the files in the extracted NOOBS folder to the formatted MicroSD card.
Now eject the MicroSD card and insert it into the Raspberry Pi board. Connect your HDMI cable from ...