LUA

if part is touched

--example if something is touched like a part. it is gonna do something to the humanoid

local part = script.Parent  --this is the part... put the script in the part


part.Touched:Connect(function(player)   --this is when the player touched the brick. we are also gonna name it player
	local hum = player.Parent:FindFirstChildWhichIsA("Humanoid") --here we gonna check the humanoid
	if hum then -- here we gonna check if it is a humanoid
		--code: example... you can change the health, walkspeed , jumpspeed and more
	end
end)

How to get a player if a part is touched

local Players = game:GetService("Players")
local TouchPart = workspace["Part"] -- assign a part to it

TouchPart.Touched:Connect(function(touched)
    if touched.Parent:IsA("Model") and touched.Parent:FindFirstChild("Humanoid") then
        local Player = Players:GetPlayerFromCharacter(touched.Parent)
        if Player then
            -- do something here
        end
    end
end)