There is now a free Ukrainian course on Open Learn
https://www.open.edu/openlearn/languages/introduction-ukrainian-language-and-culture/?active-tab=description-tabI think it is particularly aimed at people who have contact with Ukrainian refugees but I am finding it interesting as someone who knows Russian and is interested in that part of the world in general.
I have done the first two weeks of the five week course. I had started learning Ukrainian on Duolingo. This Open Learn course is generally better. It is more contextualised and teaches in a more varied way that the “sink or swim” approach of Duolingo - I wonder if I could have coped without my knowledge of Russian because nothing is really taught on Duolingo.
The Open Learn course has discussion forums and they provide some social learning but they have not been used much yet. There has been some feedback and I hope that as more people join there will be more interaction.