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Your LimeSurvey version: [see right hand bottom of your LimeSurvey admin screen] version 5.6.15
Own server or LimeSurvey hosting: own Server
Survey theme/template: fruity
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Hi everyone! How to set one survey to model or templates, this template can be view and copied by other users. the target is set an existing survey as a template, and to give other users the ability to add or modify new content based on it, which reduces the time to create a survey, thanks!

Please, do not double post.
You asked this in the German part, too, where you got an answer.

Joffm

Sorry! I thought the different language sections would have users from different countries...

In theory they might have, but in practice most respondents from the Germany forum also respond in the English forum. But even if this would be different people, you still might cause double the work, as someone from the German forum might already have responded, but the people in the English forum might not know that. So choose one language forum first and should you not get a response within a couple of days, you can say that you will also try in the other forum. Ideally leave a link between the two posts so that helpers can see what is going on.