We moved into our house on April 1st signed the lease for April 1st but paid for the house march 19th the landlord went in and scratched the date and changed it made us pay more money and to top it off the lease is for Illinois and we live in Indiana she has done nothing but give us pain since we moved in she has even went to my husbands job early to try and get rent after being told to stay away she has came in our house when we wasn't here and we are just tired of it and want to move how do I write a letter or what do we do

No, sorry the landlord merely asked you to pay more, if you had a written lease there was no obligation to do so.
The state the lease is written for, as long as it does not have any terms not allowed has no bearing. I will assume the house address is correct.

They can not merely scratch out the date unless you and them both initial it, so the original date is still the valid day.