How do I remove background color after importing

Hi I’m new to toon boom
Im using toon boom studio 4.5 all of my images have a bright green background I imported them and i vectorized them or whatever but i cant erase my background color I cannot figure out where the chroma keying tool is and if i choose to erase color under the fill tool it erases the entire image. help?

also can someone tell me what the newest version of toon boom is or best version is cuz i think mine is older maybe and i need to upgrade but i dont know to which one.

Unfortunately, there is no feature in Toon Boom Studio to remove bitmap color in range. If you import it as color as texture, you can erase some parts with Erase tool.
I would say Harmony since Harmony has a feature for example But this is only in Harmony premium.