There is no uniform process for what happens next.
The purpose of Foreclosure Intervention is to give the parties to the foreclosure lawsuit an opportunity to engage in Loss Mitigation as a way to try to resolve the foreclosure before the case moves forward.
The Servicer or the attorney may send you a Loss Mitigation application to fill out and submit along with supporting paperwork such as paystubs and bank statements. You should check with the mortgage company's attorney to find out if you will need to fill out and submit documents to be reviewed for Loss Mitigation.
If the mortgage company's attorney asks you for documents or more information, you should make every effort to get them what they ask for as soon as possible, or they may deny your request for Foreclosure Intervention.