Cryptographic support on HelTec devices RSA.h

I would like a LoRa device to be able to compute a SHA256 signature. I found Arduino examples that use RSA.h

My code does not find this header file when I compile. My board design is an HTCC-AM02 CubeCell Module design, but my design could switch to ESP32 based on the Wireless Shell V3

I also read somewhere that the ESP32 has hardware support for RSA and that without hardware support Crypto algorithms may not be possible on an embedded device.

QUESTIONS
Should a CubeCell design (AM02 or AM01 V2) be capable of doing RSA signatures?
Would I need to switch to an ESP32 based design?

I am primarily asking for a “yes it is possible” or “no it can’t be done” so that I don’t waste a lot of time trying to do something the device is not capable of doing.