Quotes delimit strings: it a string starts with a single quote, it also ends with a single quote. Your
element contains single quotes, so the system tries to work out what you are saying:
str = '...'video'...';
And fails to understand.
If you want the word
in the string, remove the quotes:
echo('<iframe width="1000" height="515" src="'.$fila['url'].'" frameborder="5" allow="autoplay;
encrypted-media" allowfullscreen class="video"></iframe>');
If you want something else, you need to work out exactly what first!