>>528226395
It's like shooting bots on an FPS to prepare you for multiplayer.
Sure, you can get a feel for the game and a basic grasp of the mechanics but fighting bots is noting like fighting people.
It just takes time. Fight some other C/D ranks in lobbies. Do long sets. Keep rematching over and over til they leave. But don't try to fight people above you unless you are very, very comfortable with your character and know their kit reflexively. It's not that fighting better players isn't theoretically good, but if you don't understand the game yet you are just throwing yourself at a brick wall and you get too frustrated to play normally.