Your space homepage should summarize what the space is for, and provide links to key resources for your team.
If you're working on something related to your team - project plans, product requirements, blog posts, internal communications, you name it - create and store it in a Confluence page. Confluence pages offer a lot of flexibility in creating and storing information, and there are a number of useful page templates included to get you started, like the meeting notes template. Your spaces should be filled with pages that document your business processes, outline your plans, contain your files, and report on your progress. The more you learn to do in Confluence (adding tables and graphs, or embedding video and links are great places to start), the more engaging and helpful your pages will become.
Learn more by reading Confluence 101: organize your work in spaces