Don't worry, the more you use words like mole and stoichiometric coefficient , the more you will grow to understand them. For reactions in aqueous solution, the reaction always proceeds in the direction that produces a solid precipitate, that is, a compound which is not soluble in water. So you have three tables to learn. Both sodium chloride and silver nitrate are soluble in water. If I swap the names I get silver chloride and sodium nitrate.
Silver chloride is insoluble and sodium nitrate is soluble.
So I know if I mix a solution of sodium chloride and a solution of silver nitrate, an insoluble precipitate of silver chloride will form and sodium nitrate will remain in solution. Both are soluble in water. The products, sodium nitrate and potassium chloride are also soluble in water. The solution just has sodium ions, potassium ions, chloride ions, and nitrate ions floating around separately. None of the ions will stick together to form a precipitate so no reaction occurs.