So the first problem was to import stuff from Blogger. The trick is to “archive” the blog over at Blogger.
Then the second step is to import it over at WordPress using the Tools/Import menu
It seems like the work flow is to select a block which seems to have the right formatting options, and then change the text and images.
It’s quite a complicated system compared with Blogger. There’s a lot to learn considering I just want to use it as a notebook. But on the other hand it seems very comprehensive.