Hi,
I'm assuming you're talking about a two-hand piano piece. To have barlines that connect from the top of the treble to the bottom of the bass staves,
(1) Click on the "Staff symbols" tab
(2) Click the "Add braces or brackets" (first button on left)
(3) Click either the Braces or Brackets button, whichever you prefer
(4) Click in the score just on top of the top staff's clef symbol.
(5) "Grab" the bottom of the brace/bracket with a mouse click-drag and drag it to the bottom of the bass staff (if you have multiple staves for a part, you can encompass those in a bracket or brace as well).
The braced/bracketed staves will now have the line going through the score.
(FWIW, the "line through" issue was resolved in this fashion after a lot of users asked for a way to not have the line through because of lyrics.)
Enjoy
Sherry