In our 2016 taxes i did not put in our eligible expenses for home accessibility reno tax credit, because it was last year can I add it to this years taxes?

The Home Accessibility Renovation credit must be claimed in the year that the renovations were done.  You would have to amend your 2016 tax return.  I have included a link below which explains how to amend your past years taxes using your CRA my account.

https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/change...