A Notice to Vacate is merely a letter from the landlord. It is a demand letter, demanding that you move out. The letter ALLEGES that you, as tenant, have breached the lease.
If you move out, following receipt of a Notice to Vacate, you will be breaking the lease, even if did not breach the lease in the way the landlord claims in the Notice to Vacate.
The Notice to Vacate is a letter or notice that the landlord is required to serve the tenant prior to filing an eviction lawsuit. The Notice to Vacate will demand you vacate the property within a certain length of time. Most TAA leases say as little as 24 hours notice is sufficient. The general rule is 3 days notice unless a different length of time is specified in the lease. The landlord must wait until the specified time expires before it may file an eviction lawsuit.
If you have not broken the lease, despite what is stated in the Notice to Vacate, you will have a chance to present a defense in the eviction lawsuit. The eviction lawsuit will be served upon you and will include your trial date. The trial will be in the Justice of the Peace Court in the precinct where your residence is located.
You are not evicted until and unless the Justice of the Peace rules that you have breached the lease. The landlord must prove its case to the judge (or jury, you have the right to a trial by jury). Only if they prove their case, and after you are allowed an opportunity to present your defense, can there be a judgment of eviction. Even then, you have five days to either move out or to file an appeal to county court. You may appeal a case to county court and have a brand new trial.