While I have an unstable connection I would like gradle to download files only one after another, instead of the default parallel download mode, a preview of parallel-mode is below:

Because as it is currently none of the files gets ever downloaded to its end, it's wasting time, and time is money.
You can refer the solution shared by sterling here
And we can set the org.gradle.parallel property in a gradle.properties file (which should be placed in the projects root directory, besides of build.gradle file), just append a line like org.gradle.parallel=false to gradle.properties file.
see also: Disabling parralel threads
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With