Is there a way to make an email auto responder for Gmail

I am trying to make a code that reads my emails, check for new emails, when it sees a new email ,it forwards it to my other email and it makes a ticket (some database stuff), i can use javascript for the tickets and database,i kinda know how to make it send an email, but i never found, anywhere, a way to make it read the emails and reply to them.

if i was able to do it, i would later make it not make a ticket if someone replied to its email and it will be added as an email to the same ticket, but right know i just want it to be able to detect new emails

I know javasctipt, Node.js, a little python, a little html. i dont know if that helps, but i would hope i would be able to do it in one of those.

another question: Idk how this exactly works, but will this also be able to be hosted on heroku? so the code stays working all time.

Thank you, sorry for the stupid question

I also just wanna mention, i actually did research, all i saw was auto respond paid services, samples/examples of what a reply would look like (no code), and the free included one in Outlook, and the only code related stuff i found were only for sending emails, not responding to new emails, so it wasn't eve mentioned online, idk why no one mentioned this topic, is it not even possible to code it?