Hi, I am not good at any type of repair like this, but if I could have someone tell me step by step I could do a great job...just know it, and thank you.

Okay, I have just a regular old fiberglass bone colored tub, nothing fancy at all. The part of the drain that I push down to keep the water in the tub broke so I sent my teenage son to purchase a new one and it worked great.

However, should have known it couldn't stay perfect for long....now, the part of the drain beneath that push up/pop up piece broke. The new pop up piece was screwed in but the metal trap pieces it screws to must be old because it broke right off. Just for clarification, because I most likely confused you....the round silver circle part of the drain in the bath tub.....can that alone be replaced? If so how do I get it out of there and is it pretty much a standard size if it can even be replaced at all? Thank you very very much.