Some users may need specific support because of e.g. some visual impairment. accessibility features have to be enabled manually. Some boot parameters can be appended to enable accessibility features. Note that on most architectures the boot loader interprets your keyboard as a QWERTY keyboard.
For users with low vision, the installer can use a high-contrast
color theme that makes it more readable. To enable it, append the
theme=dark boot parameter.
Alternatively, Debian can be installed completely automatically by using preseeding. This is documented in Appendix B, Automating the installation using preseeding.
Documentation on accessibility of the installed system is available on the Debian Accessibility wiki page.