The way I see defending is as soon as you lose the ball. You need to get about the opposition BUT without pulling the team out of shape. As soon as you lose shape you have given them the key.
So, my advice is to work on reading the game. Cut the supply in to the front players. If you are conceding from range you need to get into them before any shots can be taken and make the block or win the ball.
Reading the game and reading the opponents will set you well. Find a formation that gives you cover but equally gives you some form of attack. We don't all get along with the same formations.
You can defend. Obviously people will find ways to score but that's football.
Defending is possible but definitely requires reading the game and being set.
All the best with that.
