ShareLaTeX has a variety of packages and projects including 255 journal templates. You can also create your own template/project from scratch.
Depending on what version of ShareLaTeX you have (free or paid), you can also add collaborators to a project, share a project, or copy a project.
To copy or clone a project, select the project you want to copy, click the More Button, then select Make a Copy.
More information on sharing your project: https://www.sharelatex.com/learn/Sharing_your_work_with_others
and copying a project: https://www.sharelatex.com/learn/Copying_a_project