I have paid for some expensive medical treatments for the parent and the parent lives not with us
Declaring a parent as a dependent would generally not impact their tax return. Hope that helps!
This page has very detail may help you to decide whether those expenses can be qualified.
https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-return/completing-a-tax-return/deductions-credits-expenses/line-30450-caregiver-infirm-dependant.html