I want to draw a car and house but I could not set the vertex of them even though I did draw square ,triangle and pyramid. So who can help me out in this
Your Trig teacher would probably be the best one to help you with stuff like this. I got plenty of experience using vertices and point translations in High School with a program called AutoCAD for my DDP and Architecture classes. Before that we did a lot of work by hand with Axonometric projections; this is where you draw two faces of an object on graph paper and then apply some transformations to the grid points and bring them together into a single 3D picture. There aren't any shortcuts here, developing this part of your brain is all about practice and it's much easier if you start when you are younger.