What's the best way to make a GUI in shell

from tkinter import *

You can use WPF and windows forms in Powershell...

If I understood correctly your terribly formulated question, ncurses is what you are looking for.

sixels https://en.wikipedia.org/wiki/Sixel

>>62446825
PowerShell and WPF, after 20 minutes spent on StackOverflow and a bunch of pulled hairs:

Add-Type -AssemblyName presentationframework
[xml] $WindowXML = @"
  <Window
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     Width="400" Height="200">
     <Grid>
         <Label Content="Go fuck yourself" HorizontalAlignment="Center" VerticalAlignment="Center" />
     </Grid>
 </Window>
"@
$WindowForm = [Windows.Markup.XamlReader]::Load((New-Object System.Xml.XmlNodeReader $WindowXML))
$WindowForm.ShowDialog()

Python and Tk, after 5 minutes and three Google searches:

from tkinter import *
root = Tk()
root.minsize(400, 200)
l = Label(root, text="Go fuck yourself")
l.place(relx=0.5, rely=0.5, anchor=CENTER)
root.mainloop()

Basically what I'm saying is go fuck yourself.