Bridge

Bridge is a lot more approachable when you don't need three other people at the table at the same time. This version pairs you with a computer-controlled partner against two computer opponents, so you can actually practice bidding and play without organizing a game. It's the real thing underneath, not a simplified version — you still need to read the bidding, count your hand, and decide when a risk is worth taking to control the tricks. A solid way to learn the conventions before you sit down with people who already know them.