If you're not interested in developing aircraft, you don't need to deal with repositories. The recommended way to acquire them is via the FG download page for the version you're using
3.4 aircraft download page(3.6 will appear soon with the release)
The page allows you to filter aircraft according to how developed they are, so if you don't want to try aircraft without a 3d cockpit, you can filter them out.
This contains aircraft which match the release versions (whereas external repository collections may contain aircraft working only for past versions, or for the current development version), which are automatically updated to match version requirements and for which you will get a measure of official support.
The problem with FGMembers is that collecting all available repositories gives no version control - we've seen several instances of users assuming they'd fly a particular version of an aircraft whereas the repository contained something quite different. So it's not really something for a beginner to sort out.