Choose layout margins and columns.
Indesign margins and gutter.
Assuming i guessed correctly are you trying to define the gutter widthor gutter position.
To achieve uniform spacing set your gutters to the same value as or a multiple of 1 5 or 2 for example the leading of the text.
Because adobe indesign layout pages can include column guides as well as margin guides you can establish the gutter dimensions for a variety of layout options within one set of guides.
Enter values for top bottom left and right margins as well as the number of columns and the gutter the space between columns.
Or you can update or add a gutter to an existing project by selecting layout margins and columns from the top menu bar.
Some people use gutter to describe the space between 2 columns other use it to describe the space between two pages.
Gutter widths should relate to the body text leading value.
Use margins and column guides to position content.
To adjust column guides manually drag them horizontally to new positions producing unequal widths.
Open the pages panel window pages and select the thumbnails for the pages you wish to change.