Guys! To start with, campus placement preparation has become a major challenge. The skill requirement of companies and the curriculum of colleges is no where overlapping. As a result, it has become hard to crack the recruitment tests and interviews of even mass recruiters like TCS, Infosys, Wipro etc, especially for the non-cse guys. Technical skill requirement (knowledge of programming) has been on rise since a year.
My knowledge of placement scenario has improved ever since I have attended them myself. Here is my take on what websites to prepare from.
1) India Bix - https://www.indiabix.com/aptitude/questions-and-answers/
2) Aptipedia - https://www.faceprep.in/aptipedia/
1) Geeksforgeeks - https://www.geeksforgeeks.org/
3) Javatpoint - https://www.javatpoint.com/
4) Tutorials point
Competitive Coding (for Hiring challenges and for product companie like Amazon, Microsoft, SAP labs):
1) Hacker Rank
2) Hacker Earth
Company recruitment patterns and frequently asked questions
1) Faceprep's company corner - https://www.faceprep.in/companies/
2) Hitbullseye - https://cpt.hitbullseye.com/Test-Pattern.php
Suggestion: Please donot buy materials/courses from any of these websites. A lot of content is available for free. You can prepare from them. But if you still prefer/ require some help in understanding concepts better, then you may go for them.
Also, please do share websites that might help.