How to create a public group using this?

[gaojindev]

When I use this to create group, the type is always private.
I want to create a public group or change group type later.

await client.invoke(
  new Api.channels.CreateChannel({
    title: groupTitle,
    about: groupAbout,
    flags: 1082135647,
    broadcast: false,
    megagroup: true
  })
);

How to do this using gramJS?
Or is it impossible due to TOS of telegram?

[darkdeathoriginal]

create a group like the way you do it and then give it a username.