Timer Billboard GUI help? (SPEFIC)

So basically i want a timer to start when a player touches the part from 5 seconds and in that 5 seconds my part is transparent and non touchable but i want to make a billboard gui text that count downs from 5 to 0 then refresh's to 5 when the player touches it and when it goes to 0 it refreshes again.

Sorry its hard to explain and i know this isn't a request site but now body is talking about this *timer *system i want to create.

well i have a timer gui script but idk how to make it reset but i hope this works for you and btw u need to link a text button to this and make it a billboard gui and put it in starter gui (280 is the seconds)

local time = 280

for i = time, 1, -1 do
    wait(1)
    script.Parent.Text = i
end