The correct sentence is -

Confident, desirous, fond, negligent, capable, despair ইত্যাদির পর of + Gerund (Verb + ing) বসে।
যেমন -
He is negligent of learning your lessons.
He was capable of doing the work.

Be used to না থেকে শুধু used to (Modal Auxiliary Verb) থাকলে Base Form ই বসবে।
যেমন- I used to go there in my childhood.