Termux officially does not support Android 4 (KitKat or earlier). Its minimum requirement has been Android 5.0 for years, and modern versions now require Android 7.0 or higher.
Limitations you should expect
Perform data processing or generate graphs for your paper using Python (NumPy, Matplotlib). Exporting: termux android 4
However, you can still achieve a terminal environment on older devices using "Legacy" versions or alternative apps. 1. Legacy Termux (Limited Functionality) Termux officially does not support Android 4 (KitKat