Hi I found this git hub but when I tested it it didn't work . I have a Chinese Nano with the ch340g. [link] (GitHub - jw0k/serial2ti83: A program for Arduino Uno that makes it possible to connect a TI-83 calculator to a computer) If you could help get this work that would be great thanks.
It also appears to be a 4 year old lib that is not maintained.
It seems to be a form of software serial so you may find another that works better on Chinese clones.
There is a very old thread which may also throw you some help.