“With pleasure,” said he, “though I venture to prophesy that you'll want very few hints. I dare say we shall be often together, and I should like to banish any needless restraint between us. Will you do me the favour to begin at once to call me by my Christian name, Herbert?”
This is an example of a Victorian convention. It was customary to be ever polite and formal until you got to know someone very well. Herbert asks Pip to call him by his name, and anticipates that they will be able to be informal. When they exchange first names, it is a big step in their friendship.
Herbert also reveals that he goes out to “look about him” regularly. It was common for young gentlemen to need to buy themselves a place initially. If their family could not, they would wander until they found something.
In chapter 23 we see a household run by servants, where children are raised by servants. This was very common in Victorian England. Dickens also describes Mrs. Pocket as having grown up suitably useless.
So successful a watch and ward had been established over the young lady by this judicious parent, that she had grown up highly ornamental, but perfectly helpless and useless. With her character thus happily formed, in the first bloom of her youth she had encountered Mr. Pocket. (ch 23)
In chapter 24, Pip learns that he is being groomed as a gentleman, but not for any particular profession. This was common then. Then gentlemen in Chapter 25 are likewise not impressive. They are just gentlemen, a purely Victorian construct.
Joe’s arrival in chapter 27 is an example of how accustomed Pip has become to Victorian high society standards. He is ashamed of his uncle. Joe even calls Pip sir, since he is a gentleman now.
Here Joe's hat tumbled off the mantel-piece, and he started out of his chair and picked it up, and fitted it to the same exact spot. As if it were an absolute point of good breeding that it should tumble off again soon. (ch 27)
The fact that Pip is ashamed also hits home when he returns home to see Miss Havisham, but stays in the Blue Boar instead of at Joe’s house.
In chapter 29, Pip reflects on why he wanted to be a gentleman.
Truly it was impossible to dissociate [Estella’s] presence from all those wretched hankerings after money and gentility that had disturbed my boyhood—from all those ill regulated aspirations that had first made me ashamed of home and Joe. (ch 29)
The real reason Pip wanted to be a gentleman was so he could have Estella, bringing us to Dickens’s real commentary on Victorian society. Class systems were so rigid that people could not marry for love.