it's very worth mentioning that presidential executive orders are not a magic way to get around checks and balances. just like anything else they are subject to the approval of congress
more specifically, congress can decide to defund the wall project here or take some action to deauthorize it. of course, we have a republican majority in both houses and a republican president, and Annoying Orange has veto power now, so it's probably not happening unless there's a good number of republicans that think it's bullstuff too (enough to pull together a 2/3 supermajority)
gotta say, was not expecting this to be done via an executive order