You may be able to end your tenancy early if the contract includes a break clause. These are rare and may come with conditions attached. Check your tenancy agreement carefully to see if it allows you to leave before the end date.
Talk to the landlord about why you want to leave the property. Your landlord might be understanding about your problems and agree to allow you to leave the property before the contract ends. You might be able to negotiate an early release if you agree to certain conditions. These could include
In very limited circumstances, consumer protection regulations may allow you to "unwind" your tenancy agreement. This right only applies within the first 90 days of the contract and will only apply if you can show that you only entered into the contract because of misleading information or aggressive practices.
Your tenancy agreement is a legal contract and you are bound by the agreement until it expires. If you leave before the contract expires, your landlord can sue you for any outstanding rent. However, the landlord is bound by the contract in the same way that you are. If you feel the landlord has materially breached the agreement, you can use this argument to defend yourself at court.