where is electronics and communication engineering sample question and answer download
If You are talking about Entrance exams Like GATE then You can download it after visiting the official website of GATE 2019 Which have all previous years paper. If you want to have questions for IES exams then Visit the UPSC website they have previous years paper.
If you are just preparing for You college exams then Different universities have different question paper pattern so try to get from Your senior if Not buy question bank of that university. In general, there are numerous sites which will help you for practice. NPTEL slides have very good questions, also You can search for MIT courses and solve tutorials, There are many Universities which provide content for free such as the University of Oslo.