Well done to Nithiya and JY who have sent in the solution of 843 cubic centimetres, which is very nearly correct. Alex sent in his work on this problem, which shows how he gets the right answer.

I thought of four ways to arrange things.

The different ways to cut the paper
In the blue diagram, the size could be chosen in two ways.

If the length of the paper fixes the circumference of the cylinder (so the height is across the page), then we know that 2πr=29.6, so r=14.8/π. Also, 2r+h=21 (looking at the width), so h=21-(29.6/π). So the volume is
π r2 h=π× 14. 82 π2 ×(21- 29.6 π )807 cm 3

(to the nearest whole number).

If the length of the paper fixes the height of the cylinder (think of the label as being the other way round on the page), then we know that h=29.6, so 2r+2πr=21, so r=10.5/(1+π). So the volume is
π r2 h=π× ( 10.5 1+π )2 ×29.6598 cm 3

(to the nearest whole number).

Also, in the red diagram the size could be chosen in two ways.

If the width of the paper fixes the circumference of the cylinder, then 2πr=21, so r=10.5/π. Also, 2r+h=29.6, so h=29.6-(21/π). So the volume is
π r2 h=π× 10. 52 π2 ×(29.6- 21 π )804 cm 3

(to the nearest whole number).

Finally, if the width of the paper fixes the height of the cylinder, then h=21 and 2r+2πr=29.6 so r=14.8/(1+π). So the volume is
π r2 h=π× ( 14.8 1+π )2 ×21842 cm 3

(to the nearest whole number). This last option is clearly the best.