I own an Ender 3 V2 and I don't love its UI too much. Also, it doesn't have a touchscreen and recently I switched to Octoprint for managing my 3D Printer. So, I have added a touch screen to the same.
NOTE: Not every display will work, the one I linked is working great. Although you can use any of the Rpi 3 or 4. Not sure for 5 and zeros.
Download Raspberry pi imager: https://www.raspberrypi.com/software/
Install the Raspberry pi image as per the instructions and insert your SD Card in your PC. And Run Raspberry pi Imager, the window shown below will pop-up.
Click on “Choose Device” and select your Raspberry pi.
Click on “Choose OS” , scroll down and select “Other specific-purpose OS” as shown below
The below menu will pop up as shown below, and select 3D printing .
Another menu shown below will pop up, and select Octopi
Select OctoPi(stable)
Now, select your SD Card. Be careful and select the newly inserted SD card only. After this, the below screen will pop up to customize the settings, Click “Edit Settings”.
Now set the username and password as well as Configure wireless LAN settings and Hit save. And now click “Yes” to apply the settings u just did.
It will take some time, once done. Remove the SD Card and put it in Raspberry Pi.
Place the Raspberry Pi on the back of the display and by using the appropriate HDMI Connector connect the Raspberry Pi to the display. Using one of the two USB cables connect the Display to the Raspberry Pi. Connect the power adapter to the Raspberry Pi, also make sure you are using a Good power supply to power up your Raspberry Pi.
Follow the instructions shown on the Setup Wizard and set your Octoprint, the only section that needs your attention is “Default Printer profile”. Click on Print Bed & build Volume, the second tab next to the General tab. And configure the settings as per your 3D printer.
After finishing the above steps, you will be welcomed by the window as shown below, click on the settings icon as shown below
You will see a window as shown below, Click on “Plugin Manager”
Click on “Get more” and search for “OctoDash Companion” and hit install. Once done, now search for another plugin “Slicer Thumbnail”.
Once both the plugins are installed, restart the Raspberry Pi by click on the power button as shown below:
Go to the print setting and paste “16x 16, 200x 200”. Copy and paste it (without double quotes). This will show the thumbnail on your Display before you start printing.
Connect a keyboard with Raspberry Pi and log in with the credentials that you have set in the first step. Once done, write the below command:
bash <(wget -qO- https://github.com/UnchartedBull/OctoDash/raw/main/scripts/install.sh)
and hit enter and now you will be prompted with this message “Please specify OctoPrints full virtual env path manually (no trailing slash)”. Write the below command:
/home/username/oprint
where username is the name that you have set in the first step.
Follow the commands as shown on the screen and when the API screen comes, click on “Send Request” button and go to Octoprint web UI and click allow.
Now when you will slice a 3D model in Prusa Slicer and Upload that file to Octoprint using the web interface. Select that file from your Touch screen you will see the Thumbnail of your Gcode as well.
This tutorial is on how to do the setup and there might be some changes in the features after the release of this tutorial. And I am not responsible for any harm that may be caused by following this tutorial. DO EVERYTHING AT YOUR OWN RISK. If you don't have much experience with the 3D Printer and Electronics, please consider working under someone's guidance.
