Almost all countries only took serious measures after the virus had infected significant numbers and became more difficult to control.
The only real exceptions I know are Hong Kong and Taiwan, which knew they were next due to their extensive links with mainland China. Hong Kong closed the border with China, which riled Beijing, and then only allowed limited crossings as necessary. For various reasons, there are many families with one or both parents in either HK/PRC and the children on the other side.
Hong Kong with 155 reported cases; 84 cured, and just 4 deaths.
HK a small territory but very densely populated.
I'd call that a big success. Chile and Estonia have had more infections than HK.
Taiwan 67/ 20 / 1 death (Luxembourg has more -- 77)
Can learn lessons form what they did.
Japan got a pretty good jump on things since they had the death ship floating off their coast for a while before they got really hit. Which forced them to prepare.
I'm real surprised countries didn't say, Whoa China is getting hit hard, such and such measures seem very effective, and go to masks, social distancing, shutdowns and such BEFORE the virus swept in.
Everyone was in reactive mode and waited until the virus was spreading before taking measures.