Algebra math

Well actually I have two questions .... First how do you" estimate the corridinates of each turning point and state whether each corresponds to a local maximum or a local minimum . Then estimate all real zeros and determine the least degree the function can have ".... Lol the second question is " use a graphing calculator to graph the polynomial function . Identify the x-intercepts and the points where the local maximums and local minimums occur " . Can you please them as near as possible because I really need it I didn't understand anything from what my math teacher have explained .....And thank you :) have a great day