*** Important ***
1.Go to Stores Config > GENERAL > General And go Locale Options Tab
2.Change Locale With your Scope For i18n
Example
-Scope Default Config set Locale = English ( US ) i18n = en_US.csv
-Scope TH Config set Locale or anything your use = Thailand i18n = th_TH.csv
But your don't know code file for i18n run php bin/magento info:language:list and find code for csv
when your choose locale finish run php bin/magento setup:static-content:deploy en_EN th_TH .... anything your want
Hope help for your.
In the project directory, you can run:
Launches the test runner in the interactive watch mode.
See the section about running tests for more information.
And refresh Page But not work follow this line.
hope this way help everyone.