I am a disabled and that is my only income so I don't fill out atax form. But could I deduct the interest paid on my mortgage even if I'm not required to file ?
No.
If you do not have a filing requirement, you would not be able to claim a deduction since you are not filing a tax return.
If you were to file a tax return, you would only be able to claim a deduction for your mortgage interest if the total of all of your itemized deductions exceeded the standard deduction amount depending upon your filing status.
Itemized deductions include items such as mortgage interest, taxes, and charitable contributions.
Please see the attached link for additional information on the difference between the standard deduction and itemized deductions.
Standard deduction versus itemized deduction