My under 18 daughter is approved for the disability tax credit. Do I fill in Eligible Dependent amount(equivalent-to-spouse) option or is that something different?

An eligible dependent is not affected by disability:

You may be able to claim this amount for one other person if at any time in the year you met all of the following conditions at once:

• You did not have a spouse or common-law partner or, if you did, you were not living with, supporting, or being supported by that person.
• You supported a dependant in 2017.
• You lived with the dependant (in most cases in Canada) in a home you maintained. You cannot claim this amount for a person who was only visiting you.

In addition, at the time you met the above conditions, the dependant must also have been either:

• your parent or grandparent by blood, marriage, common-law partnership, or adoption; or
• your child, grandchild, brother, or sister, by blood, marriage, common-law partnership, or adoption and under 18 years of age or had an impairment in physical or mental functions.

The eligible dependent amount is not affected by disability and is calculated automatically for you. you may be able to claim this amount since your daughter is under 18 and lives with you.