Yes, capitulate to the attacker. Cease to exist as a country, nation, people, culture. Presumably that is an option!

If Ukraine ceased military activity, why do you think Russia wouldn't continue their invasion?

Where Russia was forced out of Ukraine they left behind mass civilian graves. Bodies found with hands tied behind their backs, shot in the back of the head.

Surrendering to Russia does not bring peace to Ukraine only more suffering.

They have to fight on, Russia does not.

How could Ukraine stop the Russian invasion?

and be overrun by soldiers who kill civilians with drones, rape and pillage? No thanks