Is it possible for variables to have something similar to .Changed event?

Usually, almost every object has the .Changed event, so does variables in scripts have those? It would be very useful and easy to use

For example:

local var = true
-- if the value of the 'var' changes then a command will be triggered

Nope this is not possible. However you could do something like this

local last = varYouWantedToTrack;
while true do
  wait()
  if varYouWantedToTrack ~= last then
    -- It changed. How nice.
  end
  last = varYouWantedToTrack;
end
end);

How about this?

local previous_var = true
local var_that_is_going_to_be_changed = true
local overlap_prevention = false

while wait() do
	if previous_var ~= var_that_is_going_to_be_changed then
		previous_var = var_that_is_going_to_be_changed -- set the new value
		-- do stuff
	end
end