There is an enormous amount of information on "fat" in blood, but to answer your question, we need to know what type of "fat" you want measure.
For example, some common terms and measurements are chylomicrons (
https://en.wikipedia.org/wiki/Chylomicrons), total cholesterol, LDL, HDL, and VLDL (see:
https://en.wikipedia.org/wiki/Lipoproteins).
Do you want to measure just cholesterol, all lipoproteins, or something else? Do you need to identify the type of lipoprotein that you are measuring? Electrophoresis, which depends on the electrical properties of the various lipoproteins, was used many years ago to do that. Look up lipoprotein electrophoresis.
Early on, lipid measurements relied on wet chemistry and ultracentrifugation. The latter led to the classification based on densities that one sees today. At about that time, electrophoresis was used as an inexpensive alternative to ultracentrifugation, but it is not very accurate for quantitation. Today, measurements are based on other, more precise, and less expensive methods.
Why do you want to do this project? Is it a school assignment?
John