You might want to get interrupts (See here:
https://wiki.osdev.org/Interrupt_Descriptor_Table) and an interrupt controller (see:
https://wiki.osdev.org/PIC) working. You'll probably need to set up a clock (see:
https://wiki.osdev.org/RTC) and a timer (see:
https://wiki.osdev.org/Programmable_Interval_Timer). Then you might want write up some drivers for NICs or other devices. Or add support for ACPI or USB. If you want to support AMD64, you should enter long mode. See
https://wiki.osdev.org/What_Order_Shoul ... ings_In%3F to get a general direction to start working on and
https://wiki.osdev.org/Going_Further_on_x86 for a more specific roadmap. Hope this is what you were looking for.