He said that it was “genius”, and “savvy”, but did not explicitly approve what Putin did (recognized Donetsk, and Luhansk as independent and send military help to those regions). He criticized Biden’s response and said that it would not had happen if he was the president.
Source
https://eu.detroitnews.com/story/news/politics/2022/02/23/trump-praises-putin-genius-and-very-savvy-invading-ukraine/6908023001/ https://www.politico.com/news/2022/02/23/trump-putin-ukraine-invasion-00010923