This is a simple application demonstrating how to transmit and receive LoRa messages using the HopeRF RFM95W radio modules, which seem to use SX1276 chips:

https://www.digikey.com/short/zzfzbm

Note that these modules don't include an antenna. You can either make one out of a length of wire, or buy one for your target frequency (915MHz in this example). Either way, solder it to the pin marked ANA on the silkscreen.

For more information, check the datasheet, especially the 'register map' sections:

https://www.hoperf.com/data/upload/portal/20190801/RFM95W-V2.0.pdf

If you get a cheap radio module from the usual bargain-bin sources, it may have an older revision of the chip. You can tell by checking the RegVersion register at address 0x42. Current versions should return 0x12; if you get 0x11, this datasheet will apply instead:

https://www.rfsolutions.co.uk/downloads/1463993415RFM95_96_97_98W.pdf

This application targets an STM32L432KC "Nucleo-32" board:

https://www.digikey.com/short/zzfznf

The program requires two boards and radios: one to transmit, and one to receive. Un-comment the appropriate MODE definition in src/main.h to build each half of the application.