To answer this question properly would require a detailed survey of all of Larkins' poems. For the moment, let's consider a few of the poems most often anthologized.
"Church Going" is one example. This poem begins with a highly particular situation: the speaker enters a country church while he is biking through the countryside. After exploring the church and considering the fate of churches (and, by implication, of religion in general) in an increasingly irreligious age, he concludes that churches will never be abandoned completely,
Since someone will forever be surprising
A hunger in himself to be more serious,
And gravitating with it to this ground,
Which, he once heard, was proper to grow wise in,
If only that so many dead lie round. (59-63)
In this poem, then, the movement is clearly from particular to general -- from the isolated bicyclist to the unnamed "someone" who represents a deep-seated human desire for wisdom.
The same pattern of moving from particular to general is repeated in "MCMIV," which describes the eagerness of men to volunteer, in 1914, to take part in World War I. After describing the details of those days, the speaker concludes, in the final stanza,
Never such innocence,
Never before or since, . . .
. . . .
Never such innocence again (25-26, 32)
Here again, then, the movement is clearly from particular experiences to a general conclusion.
"Aubade," however, opens with a highly particular situation and a highly personal perspective:
I work all day, and get half-drunk at night.
Waking at four to soundless dark, I stare.
Much of the generalizing in this poem, interestingly, occurs in the middle section, as when the speaker announces, "Death is no different whined at than withstood" (40).
By the time the poem concludes, ten lines later, Larkin has returned to mundane particulars:
Work has to be done.
Postmen like doctors go from house to house. (49-50)
The structure of the poem thus mimics the poem's topic, in which disturbing thoughts occur in the middle of the night.
In another famous poem, "Explosion," almost the entire poem is made up of particulars; Larkin leaves it to readers themselves to draw their own general conclusions from the detailed particulars he describes.
Finally, one other notable poem ("Sad Steps") does indeed move from particular to general, since its final lines conclude by mentioning
. . . the strength and pain
Of being young; that it can't come again,
But is for others undiminished somewhere. (36-38)
If this very brief survey of a few of Larkins' poems is any indication, it seems best to suggest that, while some do move from particular to general, his poems move in ways that are appropriate to the particular meanings of each specific work.