Is it possible to make some line of code fire WHILE a part is being touched?

Use BasePart.TouchEnded event. It fires when the player untouches the part.

local isCracking = false

Part.Touched:Connect(function(otherPart) -- if the player touches the part
    isCracking = true
end)

Part.TouchEnded:Connect(function(otherPart) -- if the player untouches
    isCracking = false
    print("Player untouched the part. Part stopped cracking.")
end)

while isCracking do -- if isCracking is true, it will repeat printing every 1 second
    print("The part is cracking.")
end

I figured out the solution. Instead of making the code fire while its touching. I made a part that will be invisible directly on top of the ice so that when the person is on the ice, they will be inside the part above the ice.

local ice = script.Parent
local partdetector = ice.Part


while wait(0.5) do
    for i,v in pairs(game.Workspace:GetPartsInPart(partdetector)) do
        if v.Parent:FindFirstChild("Humanoid") then
            print("theres a person on it!")
        end
    end
end

This works in detecting if a person is on the ice, also being inside the detecting part. Thank you for your help but I have found the solution thanks to puppynniko's comment recommendation.

Try using in your code within each of the iceblocks:

local ice = script.Parent
local iceDetect = ice.Detector
local iceHP = 3 -- make the ice block break in 6 seconds

while true do
    if touchDetect.touched:Connect(function()(
        iceHP = iceHP - 1 -- take away one health from ice

        print("Ice has taken damage!") -- do what you want to do

        if iceHP == 0 then
            ice:Remove() -- gets rid of ice
        end

        wait(2) -- as if it's breaking to your weight every two seconds
    end)
end

this is an inefficient way but it works.