The neighbor seems to be a person of unreasonable thoughts rather a fanatic. 

If his tortures are intolerable then you issue a legal notice to him instructing him to refrain from interfering in the peaceful enjoyment of your property and also to refrain from indulging in such unnecessary embarrassing activities lest to face legal consequences with costs 

If he behaves in the same unbecoming manner, you may consult an advocate in the local and file a suit to restrain him from indulging in such activities which disturbs your peaceful possession and enjoyment of your property. 

- As per law, you have your legal right to use the common area of the apartment for day to day work and use the occupied space for your needs and none having right to lodge an objection for the same. 

- Further, the said neighbor has no right to interrupt you for using the kitchen or common area of the building for your personal use at any point of time. 

- You can lodge a complaint before the police and higher official against him for the said interruption and the mental harassment given to you , and also for threatening 

- Further, you can also send him a legal notice to him for restraining him from interfering in your personal use and occupation of the apartment and common areas , and if no positive response then file a suit for Injunction before the court. 

Your neighbour cannot object to you walking in your house 

2) no police case is maintainable against you 

You can ignore such persons 

file police complaint against neighbour for acts endangering peace under section 504 of IPC 

The police cannot interfere in such local petty issues.

You have not done any crime against him.

He appears to be mentally affected hence he is indulging in such types of cheap activities.

you may ignore his messages sent in group.

You can send him a legal notice as advised earlier  through an advocate if thing are beyond tolerance

Dear client,

Sorry to hear about your situation. This kind of circumstance might be difficult to handle, but it's important to do it in a cool, collected, and lawful manner. You have certain rights and alternatives, but common residential activities like wandering within your flat are not specifically governed by legislation in India. First, make an effort to speak civilly and gently with your neighbor. Describe your daily schedule and the nature of your activities, and show that you understand his worries. Provide possible remedies, like putting in carpets or giving him your phone information so he can get in touch with you directly if the noise starts to bother you. If the problem continues, keep a record of the dates and specifics of any complaints your neighbor has made. This can come in handy if you ever need to defend your behavior. As an additional option, you may think about adding soundproofing or rugs to lessen the effect of your regular activities. If your neighbor is interfering unjustly with your enjoyment of your property, you may want to file a complaint in India under Section 268 of the Indian Penal Code, which addresses public nuisances. But it's important to use caution while making legal threats. Sometimes, all it takes to stop harassment is a well-written legal notice from your attorney outlining your rights and the absence of any valid legal basis for the allegations. You may handle this situation assertively and legally by keeping lines of communication open, keeping records of events, and getting legal counsel.

Hope this helps you.

It is a petty dispute and better to be resolved amicably.

Else file a case under 144 crpc so that with the intervention of Police the same is solved.

Else involve the Secretary of the Society. 

Hi, Don't bother about too much. You have every right to live in apartment certain things will happen in Apartment and it is unintentional and for a bonafide reasons. If he sends the WhatsApp message you can counter them. Nothing will happen.

Dear client,

There is no express clause in Indian law that labels routine domestic chores like walking as a nuisance. State-specific rules or local municipal ordinances typically address noise-related issues. You could want to keep a journal of your everyday activities to show that your behaviors are within reasonable bounds and take proactive measures to address the situation before it arises. If you receive a legal notice, you should think about getting legal counsel. The complainant might not have a strong case unless you're making loud, bothersome noises. Maintaining an open line of communication with your neighbor may also prove advantageous. Seek to come to an agreement or compromise on the permissible noise levels during particular hours. Keep track of any proof that demonstrates your adherence to noise ordinances; it may come in handy while arguing your position. Since the police frequently get involved in serious conflicts in India, taking the initiative to resolve the issue could save needless judicial action.

Hope this helps you.

If he sends a legal notice then you issue a reply notice denying the allegations leveled by him in the legal notice. 

If he goes to the police you make your stand very clear before the police and can challenge the case if the police is proceeding with the complaint. 

You can file a counter complaint stating that he abused you and threatened you etc.

He has no case against you 

2) if he sends legal notice reply to legal notice denying all allegations made in notice 

3) if he calls police take the plea that it is your flat and you can walk in said flat 

He can’t take objection on walking only loud voice came be objected on wee hours 

- No , he has no ground for sending a notice , specially for the walking sound or for the use of common space of the building. 

- No need to take it serious . If he creating trouble then you can also file a complaint against him for harassment