It's primarily a skill game, although luck plays a huge role. In any single given hand, luck is the predominant factor in who will win or lose. However, poker players don't play a single hand. They play hand after hand after hand & and overall, skill dominates.
Poker acts like Pushups for our brain. It strengthens your brain and shields your nerve cells. Playing poker can help to rewire your brain and help to create myelin for a longer run. When we perform any activity consistently, it leads to the creation of new neural pathways.