Dear Aspirant ,
Best books for CUCET ( Central Universities Common Entrance Test ) preparation for UG courses are as follows-
1. General knowledge by Arihant
2. Test of Arithmetic by Arihant Publications
3. Quantitative Aptitude for Competitive Examination By RS Agarwal
4. Competitive English Grammar & Composition by Arihant.
5. Complete Mathematics by Lucent's Publication
6. English Grammar in Use by Raymond Murphy
7. Disha's Rapid General Knowledge
8. Analytical Reasoning and Logic Reasoning by Arihant Publications

Hope this helps !