Neither defaulting on the debt or starting a major war are effective ways to hold on to power, sheesh. He already tried to hold on to power, so you could just look at how he tried last time, that's one of the typical strategies. The other main one is a military coup.
Creating a global crisis is an excellent way to hold onto power.
Not that they started it or want it to continue, and not that I think Zelenski is anything other than a hero, but the case in point is Ukraine not holding elections since the war started.
When Zelenski told trump there have been no elections during the war trump, on camera, was delighted and said “very good”.