Filing bankruptcy is the same as declaring bankruptcy. When you file bankruptcy, the automatic stay goes into effect immediately, stopping all collection activities like phone calls, garnishments, repossessions, and foreclosures. Creditors can't even send you mail anymore!
Within a month or so, a trustee will review your case with you and your attorney.
Chapter 7: If no assets are found, the case typically closes 2 to 3 months later, and your debts will be discharged (wiped out).
Chapter 13: Your case will proceed to confirmation, where you and your attorney seek court approval. Once granted, you make monthly payments until completing your plan at which point your remaining debts will be discharged.