Here’s how to post to a page:
We’ll use the imaginary blog http://cuteslimythings.tumblr.com and create a page called Frogs as an example
1. Create your page (or go to pages to edit an existing page) and enter the tumblr blog URL plus /frogs so it should look like http://cuteslimythings.tumblr.com/frogs
2. Select page type: redirect. Next to Redirect To, type http://cuteslimythings.tumblr.com/tagged/frogs
3. Make sure you write Frogs next to Show a Link to This Page and make sure the box is checked
Each time you create a post that you want to appear on that page, you will tag it frogs and it will appear on the Frogs page (but unfortunately, because it’s a blog and not a website, your post will also appear on your tumblr home page. This is just the nature of blogs.There may be a way to hack that also, say by limiting the number of posts to that home page, but not sure how). You can also go back and tag previous posts with that same tag and they will show up on that page. Also, keep in mind that some themes do not support pages. I’m sure there’s a way to change that in the HTML editor but I don’t know how to do it.
Good Luck!