Just like there are two ways to say no, there are two ways to say yes.
Oo (Opo for formal, respectful situations) is used when answering questions of opinion or whether something got done.
Did you do the dishes?
Did you pet the dog?
Oo is pronounced like you are saying the name of the letter O twice, not as an ooh sound. O-o.
Meron is used to answer questions about whether you have something.
Do you have dishes?
Does the dog have food?
Meron is pronounced differently than it looks to most foreigners. Me is between Meh and May, and ron is like roan. Like road but with a n at the end. meh-ROAN. Sometimes you will see it spelled mayron. I believe it’s because “may” is used to say something exists. “May pera.” (There is money.) Adding the -ng ending directly on to the end of “May” would sound awkward, so it got a whole other syllable and became it’s own word.
“May pera?” (Is there money?)
“Merong pera.” (There is money.) Or, just say, “Meron,” for, “There is.”