What are my rights against wrong eviction notice, bad maintenance and landlord not paying the gas bill?

What are my legal rights in this scenario? I pay my rent promptly every month. Once, I paid late because I was out of town. I paid a late fee too and from then on, I have been paying even before the start of the month - I have proof of checks. The maintenance is horrible. The shower goes from cold to very hot and the maintenance person said it’s common in this apartment. Moreover, we get mails that the landlord has not paid any money for the gas and that our supply will be cut. I am frustrated and want to get out of here.