AWS EC2 high ping and S3 download slow

i am new to AWS.

I have some questions want to know.

my EC2 instance :

Instance type : t2.micro - windows server

EC2 region : Asia Pacific (Tokyo)

S3 region : AWS write "S3 does not require region selection."

User location : Taiwan





My EC2 ping is too high to my real-time game and S3 download sometimes is very slow.

My network type is WiFi and Cellular networks(3G&4G).

I have test with my local server, all work fine.





Questions:

1.Why my client ping EC2, the time always over 100ms?

2.How can i reduce ping under 100ms?

3.Why S3 download speed is very unstable, 50k~5mb?

4.How can i keep download speed stable?