You're confusing tactics and puzzles. They're two different things.
In puzzles you know there is a winning combination for you, so you are actively hunting for it. In real games, you have to balance attack with defense, and balance improving your position while restricting your opponent's.
Let's look at the following game:
You had a chance to pick up a pawn with Qxc3, hitting the hanging bishop, and able to follow up with Rxd4, tearing open the center and getting your heavy pieces threateningly into your opponent's camp. Instead you hung your rook for exchange with the bishop, allowing White to tear open your king's pawns. That's a big tactical mistake right there because you blundered.
You need to think not just about your plans, but what your opponent is also trying to do. For every move you want to make, ask yourself what is your opponent's best response before you actually make it. Look for specific threats and forcing sequences, and picture what the position will look like after that.