I did my ECE Diploma in 2011. How do I get a degree now in order to pursue MBA further?

MBA is a Post graduate programme, so you first need to complete your graduation. If exploring BE/B.Tech is difficult, then you can explore BA through the correspondence route and complete it in 2 years' time. Just ensure that you clear BA with more than 50% marks. Post it, prepare for CAT & then get

You need to do B.Tech or else your Diploma will also do but preference will be less and then you need to give the CAT exam for MBA colleges.