Europe is supporting Ukraine in their fight against Russia. Russia has repeatedly violated the airspace of nato nations as a test. That could easily escalate to direct conflict.

China is supporting Russia (if not by sending munitions in all other ways).

If China and Russia provide direct support for Venezuela against a US attack that’s most of the big powers in the world fighting proxy wars.

When China takes Taiwan as they promised to do in 2027 and the US supports Taiwan as they promised to do, that would yet another proxy war which could easily escalate to direct conflict.

If WW3 breaks out in earnest some future historians might argue that it was already going by this point in time.