Animation Publishing

Well,normally when i finish my animations and upload them,i just leave them like that.I’m creating a new animation- Dysebel:The animated series.
I honestly want to know how Ben 10,Gumball,uncle grandpa got to cartoon network and how sanjay and craig got to nickelodeon.
I want to know how to publish my animations without just uploading them on youtube.

I have seen that in general for a role specific to my liking with the animation houses, there is usually next to nothing in terms of advertisements in the job portals. So I’m trying out different options like through references and by upping my social profile and uploading my works in the related portals. And just hoping for the best!