Dear,

First of all, you cannot appear for NSEJS after 10th, even in 10th very few people qualify the age criteria required. Now, for NSEC and NSEP, as the level of questions vary significantly from year to year, and it only contains 10% of the questions, given the syllabus in class 10th. Instead of writing NSEP/NSEC, build your basics by writing RMO and NSEJS. NSEP for example, is much tougher than JEE due to the time constraint. Go for RMO and NSEJS, not NSEP/NSEC, but if your fundamentals of +1,+2 are clear, then go for the rest.

Hope this helps!