I would like to connect a group of questions depending on the answer to a previous question.
As an example, if the user says he is is under 18-year old, he is redirected at the end of the questionnaire on a exclusion group of questions. If he says he is above 18-year old, he continues with the next group of questions.
Is it something doable on LimeSurvey? If yes, how?
Yes, this is possible. But your description is not 100% clear which one is best for you.
There is the Expression Manager (or also conditions) to show/hide questions depending on previous questions. As you want to ask them still questions at the end, this is probably what you need to do.
Or you use quota (zero quota), but this would generally end the survey right there, so I guess this wouldn't work for you, as you still want to ask them some questions from the end of the questionnaire.
Help us to help you!
Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.
All you need to do is put filters on the groups .....
Group 1 - No Filter - Contains the Age Question ...
Groups 2 - X - Filter on Age > 18
Group Y - Filter on Age <=18
This will then only show questions inside these groups to the relevant people.