Dear Aspirant,

I understand your issue and I'm here to help you regarding that !

Generally, there are many apps and websites online offering preparation Courses for nchcm jee. But there are some of the best websites which help you do better. Not only websites, you have to grasp much more from the books as well. The main key to success is solving the previous year question papers. Give mock tests repeatedly so that you can know the areas where you are not strengthen enough. I also mention some of the website links below as follows,

http://www.indiaeducation.net/nchmct-jee/tips-and-tricks-to-prepare-for-nchmct-jee.html

https://hospitality.careers360.com/articles/nchm-jee-sample-papers

Hope this helps you !!

All the very best wishes for your future endeavours !!