Some helpful resources to begin your studies for the FAA Small Unmanned Aerial Systems exam would be:
Thoroughly read through the Part 107 regulations ()
FAA Study Materials ()
FAA practice test (see Unmanned Aircraft General at the bottom of the page )
You can also google “FAA Part 107 Practice Exam” for a variety of helpful content from other organizations and businesses
Additionally, for some of the trickier topics like sectional charts, YouTube videos can be very helpful as well