If anyone has doubts about Trump’s ability to negotiate difficult deals, have doubts about his ability to bring peace in Ukraine, were asleep during his four years as president. The man is a miracle worker, and a tireless one at that.
Reality check, the Russo-Ukrainian War has been going on in Ukraine's southeast since 2014. This was also during the Trump years, in which he was not able to negotiate a deal.
https://en.wikipedia.org/wiki/Russo-Ukrainian_War