I downloaded the pdf file containing the keys given when steemit account sing up

This PDF doesn't contain the master key. The master key comes when you create the account.

There are some invalid information about steemit keys in this post. Can you study again and prepare this post? You can ask for help from the person who introduces you to steemit.

Sending to SBD power up.

You can't powerup steem. It should be steem.