Instead of going to heaven or hell could someone choose to just die if they want

[Mirantus]

Augustine's opinion is not a condemned heresy.  Limbo is a part of hell.  We know that the Lord descended "into hell" when he went to Limbo.  We know He described it as "paradise" when He told the good thief he'd be with Him in Paradise that day.

The good thief is in Heaven. He is officially venerated in the Catholic Church, his feast day is March 25.

From my knowledge, Our Lord descended into the Limbo of the Fathers; which is different/distinct to Limbo as we talk of it today where unbaptised infants go.

[james03]

Augustine's opinion is not a condemned heresy.  Limbo is a part of hell.  We know that the Lord descended "into hell" when he went to Limbo.  We know He described it as "paradise" when He told the good thief he'd be with Him in Paradise that day.

The good thief is in Heaven. He is officially venerated in the Catholic Church, his feast day is March 25.

Yes, he is in heaven with the other people that were in the Limbo of the Fathers, where he joined them, before the Lord took them all to heaven.  Unless you want to believe the Good Thief opened the gates of heaven:

Jesus saith to her: Do not touch me, for I am not yet ascended to my Father. But go to my brethren, and say to them: I ascend to my Father and to your Father, to my God and your God.

[Michael Wilson]

There were at one time two different Limbos: 1. The Limbo of the Fathers, which was for the just that died before the Redemption, and would have included those who passed through Purgatory. 2. The Limbo of Infants, for the babies and those who never reached the age of reason. The first Limbo ended after Our Lord emptied it by His Ascension into Heaven. The second will last until the end of the World.

[KreKre]

Are we, as Catholics, obliged to believe in the Limbo of Infants, like we believe in Heaven, Hell, and Purgatory? Is it allowed to have an opinion on this matter, or is it a dogma of faith? Most catechisms ignore this question.

I am a bit confused about this. Some say it is absolutely a dogma, because the council of Florence infallibly decreed that anyone who is not baptized and dies, immediately goes to Hell. However, here the word "baptized" must not be taken to mean exclusively "baptized by water", as that is Feeneyism, which is condemned as heresy. Pope Pius VI proclaimed that it is an error to teach as dogma that the souls of the unbaptized hate God and are punished in Hell, on account of the Original sin, though he did not condemn such teaching as heretical, he left it undefined.

Some say Limbo is uncertain and undefined. And some Novus Ordo priests outright deny it, but those I don't take very seriously, because often they have some strange opinions, sometimes downright heretical.

[james03]

as that is Feeneyism, which is condemned as heresy.

Do you have a cite?

[Michael Wilson]

Are we, as Catholics, obliged to believe in the Limbo of Infants, like we believe in Heaven, Hell, and Purgatory? Is it allowed to have an opinion on this matter, or is it a dogma of faith? Most catechisms ignore this question.

I am a bit confused about this. Some say it is absolutely a dogma, because the council of Florence infallibly decreed that anyone who is not baptized and dies, immediately goes to Hell. However, here the word "baptized" must not be taken to mean exclusively "baptized by water", as that is Feeneyism, which is condemned as heresy. Pope Pius VI proclaimed that it is an error to teach as dogma that the souls of the unbaptized hate God and are punished in Hell, on account of the Original sin, though he did not condemn such teaching as heretical, he left it undefined.

Some say Limbo is uncertain and undefined. And some Novus Ordo priests outright deny it, but those I don't take very seriously, because often they have some strange opinions, sometimes downright heretical.

Its not a dogma, but since it is the teaching of Our Lord that if one does not receive Baptism one cannot enter into the kingdom of Heaven:'

Jesus answered: Amen, amen I say to thee, unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God.
[John 3:5]

So obviously unbaptized babies cannot enter into the Kingdom of Heaven. Now the alternative to Heaven is Hell, but since Hell is for those who have committed mortal sin, the babies cannot go there, so there is only one place, Limbo of the infants.
The Catechism of the Council of Trent teaches that one should not delay the baptism of infants because unlike adults, (who can be saved through B.O.D. and B.O.B.) they have no other means of salvation.

Baptism Of Infants Should Not Be Delayed

The faithful are earnestly to be exhorted to take care that their children be brought to the church, as soon as it can be done with safety, to receive solemn Baptism. Since infant children have no other means of salvation except Baptism, we may easily understand how grievously those persons sin who permit them to remain without the grace of the Sacrament longer than necessity may require, particularly at an age so tender as to be exposed to numberless dangers of death.

Feeneyism is a heresy because it denies B.O.B. & B.O.D. And because it denies the necessity for Catholics to submit to the teachings of the magisterium.

[Santantonio]

Good background on the two limbos:

https://catholicexchange.com/whatever-happened-to-limbo/