Is "BPI M3" a Linux single board computer? A quick google search turns up "Banana Pi M3 A83T".
This is a forum about Teensy, which is a microcontroller-based board normally programmed as "bare metal" from Arduino. No Teensy runs Linux.
Maybe better to ask on a forum about Linux? If this is a Linux-based board, at least you've have a better chance of finding help if you post on a forum which is about Linux for embedded applications.
But that alone isn't all you need. Your question is woefully lacking in information needed for anyone to help. You mention a touchscreen and its vendor, but how do you imagine anyone reading your message will know which touchscreen and what vendor? Nobody can see the devices you have, nobody can know how you're connecting them, or what you're trying to accomplish unless you give details. Even on the correct forum, a question like this usually is impossible to answer. Don't make generous people who want to help you have to guess the details. Put more work into your question so it has enough info. And find a forum where the topics are about the actual board or at least type of board you are actually using.