Graphing linear equations is pretty simple! The standard format is y = mx + b, where m is the slope of the function and b is the y-intercept, where x is equal to 0. You would solve the problem you mentioned like this:
y = -3(-2) + 5
y = 6 + 5
y = 11
So your point in the line for this equation is (-2 , 11). Since you need two points to graph a function, you can use the y-intercept, which in this case would be (0 , 5). To graph, just draw a straight line connecting these two points.
Hope this helps!