As an ex-Catholic, that is not the way it works in Catholicism.

There is no such thing as true absolution for confession of mortal sins. The only true way for absolution of mortal sins is through continuous good works, and even that does not guarantee your place in heaven. More than likely the best you can expect is that you will end up in purgatory, in continuous repentance until Judgement Day.

That being said, one of the most common ways to gain this kind of absolution historically is through massive monetary donations to the Church, so let's not give the Church too much credit here, but let's also not flanderize it.