Capital + Liabilities = assets is the basic accounting equation. The fundamental accounting equation, also called the balance sheet equation, represents the relationship between the assets, liabilities, and owner's equity of a person or business. It is the foundation for the double-entry bookkeeping system.
Creditors are a liability. Creditors means the persons to whom business owes money. Creditors are the persons to whom the money is payable by the business in future. So it is a liability of business towards creditors to pay them in future so it comes under current liabilities in balance sheet.
Owner's claim on total assets is equity. Total claims include liabilities, which are all the debts that the business owes but has not yet paid out, as well as owners' equity, the value of the business that was granted by owner investment.