The concentration of a solution can be expressed in many ways, including grams per liter, etc. When the concentration is expressed in terms of moles per liter and the solution has one mole of the solute in one liter of the solution its concentration is 1M.
A solution with a concentration in terms of molarity of 1.2 M can be made by dissolving 1.2 moles of the solute in every liter of the solution.
To make 6.7 liters of solution of copper (II) fluoride with molarity 1.2 we need 1.2*6.7 = 8.04 moles of copper (II) fluoride.
The molecular mass of copper (II) fluoride is 101.543 g/mole.
The mass of 8.04 moles of copper (II) fluoride is 101.543*8.04 = 816.4 g.
To make 6.7 liters of a 1.2 M solution of copper (II) fluoride, 816.4 g of copper (II) fluoride is required.