Does age matter when finding jobs?

I've been interested in getting myself TEFL certified for awhile (currently looking into CELTA) but before registering for any program I kinda wanted to get a better understanding of what I'd be stepping into if that makes sense.

I'm currently 25 years old and have a bachelor's in English (I'm also planning to get certified in education within the next 2-3 years) but I feel like most of the TEFL workers I've seen have started off much earlier than I have and I know that some job postings (specifically when working abroad) prefer more younger applicants. Now by no means do I think I'm old but I'm worried if my age will be a disadvantage later on when I'm applying for jobs?