My Ability To Learn Spanish

I have also wanted to learn Spanish for a very long time. But seeing this video also makes me wonder if it is possible at my age. My boyfriend’s grandfather is 81 and he speaks fluent Spanish, they have tried teaching him English for the 16 years that he has lived in America but as much as he has retained he still cannot speak fluent English. He only knows the basics such as how are you, hi, hello, etc. It is probably because of how old he is and because he is at the high end of the spectrum where the ability to learn another language is nearly diminished. Then again I feel like if you are at the age where your ability to learn a language is decreasing but you already speak multiple languages then you may not be classified into this group?