Europe as a continent has been doing its level best for the last 70 years to avoid war (failing miserably with the former Yugoslavia but other than that they've managed). There is zero chance that any European leader other than some idiotic, jingoistic types will intervene, and that's truly sad, but if conventional warfare happens on the continent again it'll be because Putin would be dragging countries into it.
Which by the way, what a megalomaniacal show of force. A war, and for what purpose? Because you didn't want NATO on your doorstep? Congrats, now you share a border with NATO Poland. A former KGB man should never have been allowed anywhere near power, especially one as unhinged as him. Not even Russians support this war tbh.
As for sanctions, again, Putin has a lot of Europe by the bullhorns. Either through direct funding of the governing party such as in the case of the UK, or through gas pipelines, like Germany or the Netherlands. I still believe we should sanction Russia completely, even though it will definitely make our current cost of living crisis far worse, but I think that's a small price to pay, however, considering Boris Johnson is fanatically in love with Churchill, he's been a bit of a soft touch here.
It's depressing and I feel terribly for everyone directly impacted, however I also think it'll be over fairly soon because Russia as of now has already secured a direct connection to Kyiv, and the Ukrainian army in terms of numbers alone cannot really compare.