Great Defence stats system?

Can someone help me make script that check how much damage player take and convert thise damage to exp,like:when npc attack player and deal 25(- 25 Health) that damage converting to exp based on damage(25 exp). dont know how make Damage deal to plr checker and not sure how convert this dmg to exp.Leaderstats is game.workspace:FindFirstChild("leaderstats).Exp.Value I newbie to roblox script,srry if my question is not correct