Am guessing there is a vent line on the gas tank somewhere. Run one line from the vent to one of these:
https://www.summitracing.com/parts/ado-215-153?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-acdelco&gclid=Cj0KCQjwvOzOBRDGARIsAICjxofghIGrtbGsHnp_X748 MIomo0nJXk3d7gWgu0bIuBphKw40fQ08GIoaAmIBEALw_wcB
Run another line from the charcoal canister to the crankcase breather hose (or PCV line) to the air cleaner (carb).
Once that's in place, install a non-vented gas cap.