How to stop a specific extension from loading during boot?

[AmarD]

I managed to install an Intel-graphics extension which made my screen go blank immediately.
 I did a hard reboot and everything went fine until loading extensions.
I had the blank screen again.
How do I stop that extension from running at boot so I can Uninstall it.
Thanks in advance.
*****
I made a video of it
https://youtu.be/jkbDq_uTDuI

[Rich]

Hi AmarD
When the boot loader comes up, edit the command line and add the boot code  base. This will prevent all extensions
from loading. Then delete the  Intel-graphics  extension from your  tce/optional directory. Reboot and your Gui should
be back. Then remove the line that contains  Intel-graphics  from your  tce/onboot.lst  file.

[Rich]

Hi AmarD
You need to remove the following 2 extensions:
graphics-5.10.3-tinycore.tcz
xf86-video-intel-i810.tcz

[AmarD]

Thank you for the prompt response.
Boots again properly.