With a free account you can't connect more than three social platforms. So let us first make this clear, do you want to have a paid account with Hootsuite? If not, we can choose three from your list of five. It is really easy to understand the scheduling process in Hootsuite. You can set the time, date for a post and work on. Just open your account and try around. It will happen. Moreover there is Google always to guide you, and Hootsuite has their own blog to guide you.
However if you want clear concise, well defined contents for your social media, let me know. We can work to build on your viewers.
For related posts, there is also IFTTT. Search for it. This is also a helpful tool that will help you cross post content to multiple social platforms simultaneously.
Let me know what you want.
Soma