Assigning Numbers to a Campaign

Hello, We just had our Brand approved yesterday, still waiting on the Campaign (submitted yesterday as well). At what point do we assign the associated phone number(s) to the Campaign, only once it has been approved/registered? Do we list our RingCentral main number or any that we use? (Initially I thought we were told main number, and that RC would link the numbers as needed, future numbers, etc.). We are a new customer so we have not "migrated" our numbers yet form our old provider (afraid to lose texting capabilities while this TCR confusion was going on). So, assuming our Campaign is approved, what is the next step, do we need to get Implementation involved first? Is there a video or tutorial for this last step? Thank you very much!