Some good NDA coaching institutes in Kerala are:

• Victor Growth Institute(Trivandrum and Ernakulum)

• Cavalier India Defence Career Academy, Thiruvananthapuram

• Nirvana Institute for Competitive Exams, Thrissur

• Saradhi Center for Excellence, Cherathala

• Colonel Jons Academy, Ernakulam

• Oceanic Venture, Ernakulam

Hope, it helps!