Hello there! 

Greetings!

You need to build a strong foundation first for that first read the chapter some basic principles of organic chemistry,  no need to go through the bulky books , go through the ncert , it's good and try to understand the basic concepts.  Actually students tend to skip the beginning of the lecture and early chapters of material because it’s “background” or “really easy” and jump into the material and then they don’t understand.

You should prepare mind maps.  In the course of organic chemistry, you will find many reagents. Some are reducing agents(LiAlH4), some oxidize(O3), while some dehydrate.(conc. H2SO4). Know what they do, make a list, and remember them.

Make a chart of reactions of a specific class of compounds to master organic chemistry. You can start with benzene. The most important thing is to do it by yourself.

Don't memorise rather understand.   Memorization is; overall, a poor strategy that is resorted to when people haven’t planned ahead sufficiently and have to cram the night before an exam. There are; however, certain aspects of the course that require memorization – like nomenclature terms, reagent names and acronyms, functional groups, and so on. While some students might get the hang of it after a few weeks of the course, others might have to resort to flash cards or other memory-centered devices in order to remember the course material. There’s nothing wrong with that, as long as it’s coupled with a dedication toward understanding the deeper concepts.

thankyou 

Hello,

Study prganic chemistry the most, that is, even more than your favourite subject. The more you study it, the easier it will be for you. 

About remembering the reactions, practicing is the only way. Study them and write them in your copy, repeatedly. Concepts will be clearer to you in the process.