Since glass comes in various widths, you need to figure your width x length etc. You have to figure 1 layer for the top and underside of the deck. And one layer for the inside and outside of the hull. You need to measure the hull at the middle. Then most builders put an additional long narrow (football shape) 2nd layer on the bottom. Most factory supplied kits furnish 4 oz cloth.

Two gallons of resin and one hardener for 2-1 epoxies. You may have a little left over but you won't be worried about running out along the build. Most epoxy suppliers have a 3 gal kit just like that.