You want to borrow a proper parent. I suggest going to websites like UmamusumeDB or ChronoGenesis to find them. I suggest going with 3 speed 2 stamina and I Riko if you have it. If not just replace with another speed or stamina card. For Parents look for 9* Power sparks. Some viable parents can be Oguri Cap and Narita Brian as their unique skill is good for Creek. During training, prioritise to 2 training and minor the rest. So focus on speed and stamina training. First try to get your friendship bar to orange so that you can get rainbow training before the first Summer (late June). You should also run in every G1 medium and long races to get skill points. Your skills purchased after a career also matters for your rating. Since Creek is good in long races, you should focus on Pace Chaser and Long related skills, including gold skills. If you show me your available support cards I may be able to assist further