There is a pod of eggs in my fish tank help!!?

[Anna (The Voter Kid)]

I have a standard fish tank which has 2 goldfish and a snail in it, I got 2 fish but one of them died so I got another to replace that one on Friday, so I've had this new fish about 2 days and I noticed a pod on the side of the tank and it has about 25 balls in it which I assume are eggs. What I want to know is how long till the eggs hatch? Am I able to clean the fish tank out? and if you can how do I go about doing it the pod is stuck to the wall of the tank thanks. xx
So do snails just reproduce on there own? Does anyone know how long snails eggs take to hatch?
asif thats well scary!!