The original form I was sent says Form 1099-R at the top, but at the bottom left it says Substitute Form 1099-R. Do I file it as a substitute form or an original?

[RayW7]

Before you submit a substitute Form 1099-R, contact your employer or retirement advisor and discuss your need for it. If it was simply an oversight or the form was lost in the mail, your employer can send another 1099-R. Without a Form 1099-R, the IRS will contact your employer directly to make sure that your substitute form has the correct information.

[dmertz]

You file it as an original Form 1099-R.  Do not mark the box in TurboTax to indicate that you need to file a substitute Form 1099-R (Form 4852).  The "substitute" Form 1099-R in your case simply means that it is not printed on the official IRS form.  It has nothing to do with any need to file Form 4852.