Hello guys just need more info, opinions, thoughts on this, is a tax declaration of real property enough proof that your are the owner of a certain lot/land?

If you are familiar with a tax declaration at the lower portion of it there is a Memoranda then it says” Mort for PhP 50,000 Rural Bank of Batangas as per instrument executed by<my ate’s name> on june 20, 1987” What does this portion mean?

By the way the document is on my ate’s name.

How does it differs from a title? And how can she get a title? What are the necessary requirements and what branch of government is doin this stuff?

Thanks