My post will be strictly about novel publishing since I know nothing about comic publishing or how it might differ LOL
To add on scammers warning, be VERY aware of what's called a Vanity publisher. They're "publishers" who will ask you to pay for a service in order to be published. Unless you're self publishing, never ever ever pay for a publisher to do anything. Money flows to the author, not from it and the point of getting a traditional publishing contract is that they take on the financial risk of publishing the book. The majority of the time you're paying for these services to get ripped off. You will get crap editing, crap cover, crap marketing, and still lose a percentage of your sales on top of paying them to publish you.
It is extremely rare for someone to be approached by a legit publisher. Your book or comic will have to be absolutely exploding in order for a legit publisher to take notice. If you are approached, do your research and tread carefully.
I remember the first time I was approached by a company on Wattpad. Now I knew I wasn't ready to publish because I hadn't edited the book they were interested in (and they actually took time to name the book by name which is VERY rare for those kinds of messages. Usually it's a generic "dear author we think "cut and paste of name if they even take time to do that much" would be a good fit. Contact us blah blah blah") so I ignored it. But then a thread about said company showed up on the forums so I decided to go ahead and follow it while looking into the company. And oh lord, the editing of these supposedly professionally published books was ATROCIOUS. Like they had errors that a basic entry level editor should catch. If I, a dyslexic nobody writer, can spot the problem then surly an entry level editor could. And the thread about them reflected how spammy they were being at the time. That was my first true interaction with those spammy scams.
So just do your homework. Research and ask questions if a publisher does approach you. People want to avoid the querying trenches, and I don't blame them because I did 4 queries before I realized i was not mentally ready to actually pursue publishing for real, because it's a long and thankless process that will lead to tons of rejection. But when it comes to publishing there is no quick answer. Even self publishing is going to take a lot of work if you're doing it right. It won't be as simple as upload book and watch sales roll in unless you're really really really lucky.