I have had bad constipation after after trying multiple times to go i noticed my faeces were dry and cracked looking could that be dehydration and should i seek medical attention?

Can give Dr. a call: Each person with constipation needs to be sure there is no other disease causing it. If constipation is just due to slow movement of the food and poop through the gut, the things people try include vegetables, water, fiber-with-water, prune juice, prunes, polyethylene glycol, Senokot or other senna, milk of magnesia, other laxatives... A doctor can evaluate and consider meds like Linzess.