I do not have the lease before me and so, can not give you an full answer to your question. I can give you information on how most leases work.
Once you signed the lease you became obligated for the entire lease term. Some leases have a rescission (cancellation) period, but it is usually about three days, so if you did not cancel in writing within three days, you have missed that opportunity.
One of the lease terms may have a means of terminating the agreement. If so, you should look to that.
Speak with your landlord. You might be able to modify the lease to reduce the rent or come to some agreement about early termination. Usually the landlord would rather have a clean break and find a new tenant than fight with a tenant who is not paying the rent and will not be able to do so in the future.
The statements herein do not create an attorney client relationship.
Another solution is to sublet the premises. You will still be primarily responsible for the rental, but someone else living/doing business there will pay the rent.