I just googled and got this
https://www.the-star.co.ke/news/fact-checker/2022-03-09-video-shows-climate-demonstration-not-body-bags-in-ukraine/
It was fact checked and found this:
Footage from a February 2022 climate policy demonstration held by the activist group “Fridays for Future” in Austria is being miscaptioned on social media by users who claim it shows “crisis actors” in Ukraine.