In Redactor I put some content but I don’t know why Inline CSS is not load? Is there any way to solve this problem?
You should first go to the Settings > Fields
Then click on the particular field in which you have selected the Redactor as a field type.
Then you can see Advanced option at the end of the page and Uncheck "Remove inline styles" options there.
So Redactor Editor will not remove inline CSS from your added html content.