How to sign-up network account

I am developing that using backstage API.

I have read reference about network account but do not know how to sign-up

https://developers.taboola.com/backstage-api/reference/network-accounts

As I investigated, firstly sign-up as advertiser account, then Taboola internal team will contact for creating network account if my advertiser account is eligible

Anyone that owned a network account please help to clarify below points

Taboola will provide me an Account Manager then I create network account by myself or concept of Account Manager is from Taboola so they will create network for me
If Account Manager is from Taboola, they request me different email address

Thank & Best regards,

Phu.