Yes, it certainly is possible to get a seat in AIIMS Delhi by studying for just 5 months given that you have a vague idea of your syllabus and are not completely clueless. Firstly abandon all distractions that might sway your decision especially give up on social media completely. Follow the following tips to achieve your goal
Physics
Chemistry
Biology
GK: This section can be prepared in the last 2 months by reading newspapers and solving online quizzes.
Logical Reasoning: This does not require any preparation and you can just solve it in your free time
Test Series: Purchase some good test series and check your preparation. Identify our weaknesses and work on them.
If you are adamant about AIIMS, it's recommended you focus less on your boards and more on AIIMS preparation. Also, getting into AIIMS requires much more than just dedication. It also depends on your luck. So it's better to keep all options open as there are many other top medical colleges to consider too.