The short answer to your question is that people of all religions (Catholic, Protestant, non-Christian, etc) and no religion can go to hell.
God does not send people to hell simply for not being Catholic. it is a more complicated question than that and the current Catechism (which is more complex than the simplified Baltimore Catechism that was posted) recognizes that Protestants may actually be in communion with the Catholic Church in various ways, such as through participating in sacraments that the Catholic Church recognizes. For example, the Catholic Church recognizes the Trinitarian baptism of a number of Protestants. A Protestant might also marry in the Catholic Church.
The state of mind of the person who is deceased, which is something known only to God, is a large factor, as is how they lived their life in general and why they were Protestant. Obviously if they are Protestant because that’s how they were raised by their parents, it’s a different situation than if they were raised Catholic and willfully turned their back on the Church.
It is not as simple as “You’re Protestant so you’re going to hell unless you convert.” it seems quite possible, even likely, that there are Protestants who went to heaven and Catholics who went to Hell. In any event, we do not know with certainty where any particular person might end up or has already ended up, as it is a decision made by God, so we need to avoid acting like we know for sure that anyone, such as a Protestant, definitely went one place or the other.