Two options to consider:
1. Paragraph style with tab stopsEdit > Styles > New > Paragraph Style
Tabs and Indentation: Add a tab stop (click on the ruler)
Set the Tab to be 'Right', set the position to your margin width
Set the fill character to be dot or underscore ...
Hit Done
Apply this paragrpah style to the 'questions' you want to have a user submission part - after the text hit 'tab' .
2. Manual linesCreate your text - don't add anything for where the answers are going to go
Insert > Line
Draw a line on the page (doesn't matter if it's not horizontal)
Properties: set the rotation to 0.0
Move your line to where you want it (use align to margins). If a line is too long or too short, select the line, hold the Ctrl* key and drag the start anchor where you need it
If you want to get fancy and have all lines equally spaced out (I would - the human eye is remarkably sensitive to misalignment)
- Draw one line .. place it in line with the top most question
- copy and paste the line .. for was many times as you have text lines on the page
- move one of the lines to the bottom most text line
- select all of the lines (but not the text frame)
- Align and Distribute > Distribute > Make vertical gaps equal
- Align and Distribute > Align > To Margins > Align right
- Delete any 'line' you don't need. adjust length of lines as above
* Ctrl key on windows .. locks the resizing to specific grid, makes it easy to keep horizontal, don't what the key is on Linux