Using Linux on IOS
ISH is a project that uses usermode x86 emulation and syscall translation to get a Linux shell operating on iOS.

iSH will install like any other app on your iPhone or iPad, and you may open and close it just like any other iOS app.

Once you’ve opened iSH, you’ll see a fairly standard linux command line, with commands like ls, mkdir, cd, cat, touch, vi, wget, zip, unzip, tar, chmod, grep, chown, rm, and many more working.
Because iSH provides a command line environment, you’ll be typing a lot. Typing on the on-screen touch screen keyboard is exactly what you’d expect; a laborious experience of typing on a touch screen, so if you’re serious about using this, you’ll want to utilize an external keyboard with iOS device.
How to Use ‘apk’ to Install Packages in iSH on iOS
The Alpine linux package manager, ‘apk,’ can be used to install new software into iSH.
If you wish to add python to iSH, for example, you’ll use the following command:
apk add python
You can update packages with:
apk update packagename
You can search for packages use the following command:
apk search name
You can remove packages use the following command:
apk del packagename
iSH Update
It’s important to note that you should update iSH Shell from the TestFlight app rather than the App Store.

This is due to the fact that several of iSH’s features are reportedly not allowed in the App Store, however this may change in the future.
The developer updates iSH Shell frequently, so simply open the TestFlight app and apply any available updates for iSH Shell when they appear.
DOWNLOADING ISH ON APP STORE
Watch the video below to see how to install iSH.