I am a dropper student. preparing for jee 2020, i have passed 12th in 2018 with 59%. so which problems are coming in my path because of drop

i have passed 12th in 2018, i want to complete my UG in mechanical. i have to make career in aeronautical, PG in aeronautical but there which problems are arrived due to my drop years or gap. i am preparing for jee 2020 along with manipal (MOEUT ) entrance test & few another engineering entrance exm