Hi Sushant,

The syllabus of AIIMS UG 2018 includes subjects Physics, Chemistry, Biology and General Awareness+Aptitude. The GA and Aptitute are for 10 marks each.You should read current affairs, newspapers, Books and Authors, Science, History, World Records, etc. You can prefer R.S.Aggrawal  for aptitude and Logical Reasoning. You can practice from this book. You can also solve previous year question papers.

All the best!!