I am going to clarify first that some states do have free e-filing for the state's income taxes. The programs are designed by the states' revenue departments and you can do it directly online.
But this is not so for federal income taxes. If you search for free efiling, the results I have found are not actually "free". YOu cannot do this directly on IRS's websites.
So unless you purchase a tax software, you may have to file by filling out the tax forms and then sending them in.
This is just my experience.