Hey , As per rules and guidelines, you must have a minimum of 75% in 12th with the JEE mains be cleared . As you got only 71.6% in your boards you are not eligible for JEE Advance . But if you want to pursue the engineering only , you can go through the list of many govt. as well as private colleges  which will give you admission on the basis of JEE mains marks only.You dont have to be sad for boards result as you have many other options as well . i will suggest you some govt. colleges which have a good reputation like all the UIETs.

hi,

see there is no particular percentage in 12th need to appear in jee main exam, however if you are a general or obc category students you must secure 75% aggregate marks in 12th score for admission in nits, or cftis, also to appear in jee advance exam for admission in btech course in iits,

for sc/st category candidates required marks criteria is 65% aggregate marks in 12th exam.