Can I write a blog, and sell stuff?or
Can I write a blog, and make up stuff?or
Can I include ads in my blog?or even
Can I include ads from outside Google in my blog?
Well, there are quite a few things that are forbidden by law, or forbidden by Blogger or by Google, that will get your blog cancelled. Most of the forbidden items are common sense - or so it seems to me.
You - and only you - are responsible for content in your blog.
If you include dynamic content from other web sites, like ads, you are responsible for the content - it came from another server, but it's your blog, and you take the responsibility. Any graphic porn in the ads will get your blog TOSsed, eventually. And when you do get TOSsed, please don't post, and whine about it.
I do not post adult pics ..there are just some rotating ads which may be topless sometime ...
Blogger is a personal website publishing platform, and Blogger blogs are about people.
A blog about a business must be about a legitimate business.
Some people (aka "blog owners") may publish blogs which focus on their business - but a Blogger blog should include legal and original content about the business.
When you take content from another website, respect the wishes of the owner.
Remember too, that when you include content from other web sites, you should comply with the wishes of the owners of the web sites in question. Don't just copy and paste, without asking for permission - or at least researching the web site in question.
Be a responsible member of the Internet community.
If there's a copyright notice on the web site, comply with the requirements stated in the notice. Be a respectful and responsible web citizen.
Having written into your blog, consider how to write about your blog. There are ways to publicise it, and there are ways to not publicise it, too. Advertise your blog, but advertise it responsibly.
If your content is otherwise legal, you are permitted to publish.
Other than these restrictions (most of which are common sense, or seem so to me), and a very few capacity related issues, you are free to write, and to promote, your blog as you see fit.
Non-Google ads, content, and links, as long as it's legal, are all fine. Google encourages networking with other platforms, such as Blog This!, FaceBook, and Twitter.
Pick a subject which you know - and which you care about - and write.
Write about what matters to you, for there is your passion. And your passion will get you your readers, which will encourage you to write more. And that's the rule, here.
Write about what you know about. Just get started, now. Write some now, and more later.