The only advice that i can give you is: play ranked instead of practice, there you will get easy fights all the way to jonin-kage rank, after there you might win 1 fight and then find an overpowered team 2 ranks above you, but then you get another ''fair'' fight, if what you want to do is the arena event only, do this you will be getting 1 win and 1 lose but its viable.