Just read the book of Matthew online, it has all you need to know. If you seek you will find. https://www.biblegateway.com/passage/?search=Matthew+5&version=NIV/

Keep in mind, many times through Christ's life there were people who only heard him say one of these teachings, He did not have to stop and explain the whole bible to each of them.

That tells us the message isn't so much about a set of rules, it is a Spirit that we are called to have in this life. Treat others the way you want to be treated, and love others as you love yourself. (that is not charity*** = love yourself means wanting yourself to be better, that is how we should treat each other as well.)

If you are looking for others to share the Spirit with- just look to your local Jesus-meetup and I'm sure you will find that community you talked about =)