Now that is a cryptic request.
A short example of what you are looking for would help.
Do you want a line feed to be inserted in a calculated field in a query?
Between two fields?
In a query, you need to use Chr(13) & Chr(10)
Assuming two fields named street1 and Street2
Field: TwoStreet: [Street1] & Chr(13) & Chr(10) & [Street2]
That will return in one field
Alahambra
Mason
assuming that Street1 = "Alahambra" and Street2 = "Mason"