You don't need to licence content to post it on your website. Post it, stick a copyright notice on it, and it remains yours and you can sell it any time you want. A license only comes into effect if you want to give people permission to post it on their sites or include it in their books.
While retaining copyright retains your right to sell, that is not the same thing as not compromising the salability of your piece. Publications typically want to buy first publication right or all rights. If you have already published your content, first publication rights have already been exercised and they may not be interested.
Now, of course, if you build a huge audience by giving your content away, that might interest a publisher, because a built-in audience is built in sales. If your work is nonfiction and you don't have either top-flight credentials or an existing audience (what the trade calls a "platform") this may be your only way to interest a publisher. I sold a nonfiction book on the strength of my blog.
Then again, if you publish your content and don't build a huge audience, the publisher may take that as evidence that there is no audience for it.
In short, the impact of what you are planning to do on your ability to sell you content is much more complex than any licensing issue. You need to think through your sales strategy for the content and make sure anything you do online is supporting, not detracting from, that sales strategy.