There are two kinds of disadvantages (or conversely–advantages) that you should be aware of in chess-static and dynamic.
Examples of dynamic or changeable advantages are space, initiative and development. When you have those you must take advantage of them while they exist because they will soon disappear. That’s why they are called dynamic.
Static or unchanging advantages are things like material (being up a piece or down a piece) and pawn structure. When you have a static disadvantage like weak or bad pawns (meaning pawn islands, doubled pawns or backward pawns) or when you are down material it is your job to try to complicate the position. Do not trade down (trading pawns is ok) but try to keep lots of pieces like knights, bishops, rooks and queens on the board if you can. And try to create trouble. Keep creating threats and confusing tactical positions that cause your opponent to have to think and think until he or she gets exhausted. Often this will result in an accidental loss for them and a win for you.
Chess isn’t just about getting an advantage and then proceeding to the win. Many lost positions are saved by the simple tactic of confusing and confounding and irritating your opponent (over the board by strange moves not by continual draw offers or strange noises) until their own mental energy wears out. It’s all part of the game.