Termination from 7 year services on performance issue

Dear Team, In my case, I was called by the CEO and asked to give resignation immediately with one month notice as mentioned in my initial employment contract. During past three years of appraisal system, I was never called and updated about my KRA's even after my recurring attempts for the same and have never being given project to complete, accept what I took an initiative personally to complete except regular maintenance. I have made communications of this behavior to all ,levels of the top management including Chairman and the Human Resource Committee. there are no reverse feedback from CEO or the Committee or notice/interaction with me for my so-called non performance. I am waiting for a response from the Top Management to overrule the decision or provide an alternate solution to this issue. In the meantime, I would like to know what are the legal options available to me to take against my direct boss and the organization if need be. Thanks in advance for the Help and Advice.