At different stages, for multiples processes you'll need different tools. Here are some of the tools you can use at various stages of your journey.
Enabling self-flowing conversations sets your community on a user-led momentum. Create channels focused around your key goals and interests.
Set context for each community. Guide the user about how they can use each channel. This is essential for the user to not feel lost. You can pin the introductions to the respective channels.
You community needs a content home. The internal wiki will solve for that. Include all the community content, resources, guides, mentor details and also a member directory. If it's a learning community, you can use one of the LMS platforms to host your content.
Plan ahead for scheduling content within your community. This gives you an opportunity to drive interactions and engagement over the content.
Give your community an identity - name, purpose of the community, who is it for and why does one need it.