Tenant asking money for shelf/fittings done at shop

Hello Everyone, We have 6 shops in Chamba (Tehri Garhwal) out of which we rented out a shop and got the agreement done for that shop for the year 2016-2017. We were unable to go to renew the agreement as the shops are 300 km far from Delhi and also due to ill health of my mom and dad. In Sept 2019, we went there and revised the rent and got new agreement done for the shops which were leased and tenants agreed as well for the revised rent. However the tenant of one shop denied to hike the rent to Rs 3000/- per month and said that he will pay the existing rent of Rs 1500/- per month, do whatever you want. When we asked for vacating the shop (in Sept 2019), he said that he need time and will vacate the shop in June 2020 and took 10 months time. We verbally gave him 2 months time however did not interfered him and waited till June 2020 due to lockdown. There was no rent paid by the tenant since October 2019 and in June 2020 we asked for the due rent and to vacate the shop. In August 2020, tenant paid rent for Oct, Nov & Dec 2019. For vacating the shop, tenant asked us (landlord) to pay the amount for the fitting work done in the shop which we denied. When we asked again to vacate the shop in Sept 2020, tenant again deposited the due rent for Feb, Mar, Aug, Sept 2020 in Sept 2020 where the rent for Oct 2019, April, May June & July 2020 was again missing. For vacating the shop, Tenant again bluntly said – fitting ke paise de do shop khaali kar dunga. When we asked for the amount, he asked us to pay Rs 60000/- for the fitting work done. The questions I have are- 1. Is the landlord liable to pay the fitting charges for the racks/sliding door fitted in the shop by tenant without our permission? The old agreement clearly says that the tenant will not do any damage/construction at the property without our notice. 2. Is the old agreement remains valid in the absence of new agreement ? 3. Rent agreement done in 2016-2017 says that tenant will open shop for electrical items however when we visited the shop in Sept 2019, he was running a tuition center. Is this legal to use the shop for a different business without informing the landlord ? Since the tenant agreed to vacate the shop earlier however the shop is still is in his possession, we asked the tenant to provide adhaar card copy which he is again not giving. We are planning to file 2 cases against him – 1 to vacate the shop 2 damage to property + mental harassment (for asking us the money) + unauthorized use of shop + illegal possession of shop (not providing adhaar card copy) Will be very thankful if a proper guidance is shared.