Unity Clicker Game Locked Item

Hi, I am trying to make a clicker game.
What I am trying to do is before I reach a certain level I can't use a item.
Do anybody know how?

 

Yes. Before the player is allowed to use the item, don't make it selectable by the player. Just keep track of which level they are on and when they are on the correct level or higher, activate that item.

I know that's vague, but it has as much detail as your question.

Jay