A person with Saturn in the 3rd house takes their studies and immediate surroundings very seriously.
The 3rd house is the house of the immediate environment, contacts, the house of concrete thinking, primary and secondary education, and not-so-distant travels. And the themes of Saturn in astrology are responsibility and self-discipline, maturity, life lessons, limitations, reliability, order and structure. Accordingly, a person with this placement takes their studies and immediate surroundings very seriously.
There are several possible scenarios here. The person may find studying very difficult, requiring great effort to assimilate knowledge. If they study, they will study to the point of rote memorization. And with this Saturn, the person, as a rule, remembers dates, numbers, and events well. Emotional and associative memory does not work here, but rather the structuring, clarity, order, and sequence. If the person's Saturn has harmonious aspects to the Sun, Mercury or Venus, they will love to study, and their attitude to studies will be responsible and serious.
At the same time, there may be problems with classmates and teachers, some difficult, heavy relationships. Or the relationships may be good or neutral, but there are problems with the studies themselves. Or the person tries, studies, but has a fear of saying something, of somehow expressing themselves. Here one needs to generally analyze the chart, look at the rulers, the connection of the houses and aspects.
As for the circle of communication itself, it is limited for the person. They do not like parties. If communication, then specific, substantive, for business. Or there may be a small circle of communication, but a reliable, tested one.
The person may have no siblings, or they may have difficult relationships with them, they may not communicate at all - quite cold and detached relationships, or, conversely, the person has a sense of duty and responsibility towards them. For example, they are the eldest in the family, and they watch over them, and even when the siblings grow up, this responsibility does not disappear anywhere. Or the siblings constantly have some kind of problems, and the person always helps them: financially or in essence, or for business, that is, in fact, they are a support for them.
The 3rd house is also about travels. And here the ability to travel may be limited, or they may be infrequent, or may be purely business in nature. Or the person loves to travel to the mountains, to some hard-to-reach places, where they need to overcome themselves.
The 3rd house also includes driving, cars. The person may take a long time to learn to drive, there may be a fear of driving, but having mastered these lessons and overcome their fear, the person will never violate the rules. They will adhere to them, try to act correctly. As for the car, they will choose the most reliable one. It may be an old one, but one that has been tested by time.