Being on prep and on a strict macro count, I try to choose the most delicious yet most nutritious sources. For fat, on top of the list are animal fats - Omega 3, rather than Omega 6/9 that are found in plants.
Going for higher fat % animal sources like minced meat, chicken thighs, egg yolks or fatty fish should be a staple for your diet. Diary products that contain fat such as yoghurts, full fat milk and cheese are excellent animal fat options too. And once you've covered the majority of your target fats, you can add other fatty things you enjoy - like avocados, vegetable oils, nut butters etc.
To estimate fat amounts, I use MyFitnessPal app - excellent and very accurate.
Please remember that not all nuts and vegetable fat sources have the same amount of fat per gram. You can see in the table below, that chestnuts have the lowest fat content yet quite high in carbs:
Fat is extremely important for muscle building, fat loss and also hormone balance, especially for women. You simply cannot neglect it or take very low amounts (under 40g per day), as it will be dangerous for your health. The lowest amount of fat I've personally ever been on was 50g per day. During the off-season I try to stay in 100-150g mark.