It really comes down to the diet when you are looking to get leaner. The macros are very individual and it depends how you respond to different food types. If you want to get into powerlifting I would suggest doing a diet moderate/high in carbs and protein and lower fat. You certainly need to keep carbs in your diet so for powerlifting a keto diet is definitely not going to work.
It also comes down to timing - you need to make sure you're eating your carbs at appropriate times in the day so your training and physique will benefit from it. Pre, intra and post workout being the most important.
Adding a supplement stack like plazma and indigo3g would be very beneficial for your goals as well. You can read more about those on the supplement forum or at the Biotest store online.
Are you eating mostly clean food choices or doing more of an IIFYM approach?