So all of society is categorised into the 4 basic castes and each caste has a significantly different task to fulfill in society, which I want to descbribe here:
1. Brahmanas - The intelectual elite
The main task of the brahmana class is to search for the truth, their product is knowledge.
Brahmanas are referred to as the priest class, since that was what in ancient times the intelectual elite would "work" as. However a priest is not as we understand it something that is just religious, but in ancient times a priest was also a scientist and all kinds of that, there was no separation between that, since religion was equal to science.
So brahmanas will work as priests, scientists, researchers, psychologists, teachers etc.
Brahmans don't work for themselves, they are funded by the other classes through donations or similar like it was tradition with priests. This is important, since intelectual workers can perform best, if they do not have to worry about survival, like earning money and material things for themselves. The other benefit is, that it helps them stay clear from corruption, if they do not have personal gain in their mind.
In modern times this system has of course been corrupted and the intelectual elite are just normal workers who have to do what earns them money, which is of course detrimental to finding the truth.
2. Kshatriya - The warrior class
The main task of the kshatriya class is to protect the people society, their product is security.
The kshatriya class is basically the foundation that keeps the whole society together, since nothing can develop without protection.
Kshatriyas will work as kings/politicians, soldier and goverment in general.
Kshatriyas also do not work for themselves, but finance themselves through taxation of the regular population. Similar to brahmanas they cannot bother with daily life and earning money, since they have to specialize in protecting society. They have the highest income of all other castes, but they also have the highest duty, since in a case of war, they have to fight and for a true kshatriya surrender is not an option.
3. Vaishya - The merchant class
The main task of the vaishya class is to create wealth, their product is material wealth.
The vaishya class is the economic foundation of society, they produce all necessary products like food and other material goods.
Vaishyas will work as farmers, craftsmen, merchants, industrialists.
4. Shudra - The working class
The main task of the shudra class is to serve all the other classes, their product is human labor.
The shudra class is the foundation of the workforce of a society, they do not really do anything on their own, their job is just to do as they are told and in exchange they get rewarded with a salary. The shudra class is the only class that works on a salary.
Shudras will work anything they are offered, in most cases they probably work for the vaishyas, since producing goods requires the most human labor and the higher castes do not have much use for lower intelligent workers. So shudras will work at farms, factories, markets etc under the supervision of vaishyas, since they are not intelligent enough to be productive on their own.
From that we can see that almost everyone in our current time is really just one of the lowest class, since they just work on a salary and just do as they are told.