Thank you for that. So from the card diagram. CAN1 pins are 22 and 23 (CTX1 and CRX1), then CAN2 is 0 and 1 (CRX2 and CTX2) and finally there is CAN3 which is pins 30 and 31 (CRX3 and CTX3).
So i'm thinking to stick to CAN1 and CAN2. But AI tool said that pin 0 and 1 is also shared with USB...