If fat loss is your goal you might try tracking it using a tape measure, skin fold calipers or just take a weekly photo.
Fruit can be part of a keto diet. A few raspberries tossed onto a bowl of whipped cream is likely to be a fine keto breakfast for most people. While a bowl of peaches is probably a problem for most.
How much fruit of what type depends on your metabolic health. Do you have insulin resistance/metabolic syndrome and if so, how severe? Are you pre-diabetic or diabetic? Being more active/athletic typically increases ones tolerance for carbs. Eating a lot of protein may decrease it.
The best way to see the impact of various types and quantities of fruit is to regularly monitor your blood glucose. If your fasting blood glucose is good or getting better and you aren’t seeing much post prandial elevation then your fruit consumption is probably ok. Ketone monitoring helps too, if your ketones stay elevated you’ll know you aren’t raising your insulin to a problematic level.