To add the Recent Forum Topics widget to Blogger, follow the steps below:
Adding Recent Forum Topics Widget
Go to your forum and look at the bottom where it says Feeds. Clicking on that link, you will see two Feed links: the first being the Topics only Feed, and the other one is Topics and replies. Pick the one you need.Now, log into your Blogger Dashboard, go to "Layout" and look for the Sidebar section on the right side.
Click on the "Add a Gadget" link and choose Feed from the gadgets list. Paste the Feed URL that you copied inside the text box.
Click the "Continue" button to configure the parameters and finally, click "Save changes" to see the results.
That's it... now you should be able to see the Recent Forum Topics widget on your Blogger blog. Enjoy!