Use 
unshift. It's like push, except it adds elements to the beginning of the array instead of the end.- unshift/- push- add an element to the beginning/end of an array
- shift/- pop- remove and return the first/last element of and array
A simple diagram...
   unshift -> array <- push
   shift   <- array -> pop
and chart:
          add  remove  start  end
   push    X                   X
    pop           X            X
unshift    X             X
  shift           X      X
Check out the MDN Array documentation. Virtually every language that has the ability to push/pop elements from an array will also have the ability to unshift/shift (sometimes called 
push_front/pop_front) elements, you should never have to implement these yourself. 
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