Counter spell situation

[Man_Over_Game]

You can duck behind the wall to avoid counterspell, but you can either hold the action to cast the spell or hold the action to pop out

There's really only one way to make it work:

On your turn:
Spend Action to Hold a Spell.
Move
Decide: Release the spell during your turn, or during someone else's turn, using your Reaction.

You can't really hold your action to move, because then you'd have no Action or Reaction left to cast the spell with.