How much severance pay i can claim from my organisation - Laid Off/Industry Association?

I work in an industry association (non-profit registered Society) registered at Registrar of Society, Office of the Commissioner of Industries, Govt. of National Capital Territory of Delhi at the post of Deputy Director. I have been working there since Nov 2015. Recently i have been asked to leave the organisation as the my job position has been cancelled and my work has been handed over to another person.
I would be grateful if you could guide me on the following points:
1. How much severance pay i can claim from my organisation. In my offer letter a notice period of 1 month is mentioned from both sides employee as well as employer
2. My appraisal was also delayed. I submitted my form in April 2018 and despite repeated request there was no reply from my boss. When i asked about it i was told to leave the organisation. Can i claim the due amount also?
3. My organisation allows 7 days leave encashment at the end of year. However i have 10 accumulated leave. Can i get my leaves also encashed
4. When and how should i initiate legal proceedings if i am denied what i should get according to the indian laws.
I would be thankful for your kind support.

Dear friend,
From your description of your job position in the organization, you have to work out the remedy for your employment grievances,if any strictly as per the provisions of the contract of service between the organization and yourself. If the organization fails or refuses to comply with the exit clause of the contract and encashment of unavailed leave, it amounts to breach of contract for which you would have to institute a Civil Suit only.

Dear Umakanthan Ji
Thanks for your valuable advice.
What about the appraisal process. The salaries of all employees have been increased except mine. I have been following up with my boss on this since April 2018 and now he has asked me to leave. He always gave me some reason to avoid it. It is not a matter of performance but his own incompetence and ego. I have appreciation mails from Industry members.
Also is there a definition of Mental Harassment at workplace under Indian law. Please share the link if possible.
Thanks & Regards

Dear Friend,
As rightly pointed out by Mr. Umakanthan.M, you can claim only what is mentioned in your contract of employment. Further if you try to extract more money in terms of incremental arrears and additional leave encashment you may have to go in for a civil suit which may cost you more than what you actually get.
So try and settle the matter amicably.
Thank you,
Regards,
R. H. Kavarana
HR Manager
Mumbai