The documentation for the 2.8" display on the Adafruit shows the pinout. You should be able to see what pins they may share and if that is an issue.
2.8" Display pinout
“This design uses the hardware SPI pins (SCK, MOSI, MISO, CE0, CE1) as well as GPIO #25 and #24. All
other GPIO are unused. Since we had a tiny bit of space, there’s 4 spots for optional slim tactile switches
wired to four GPIOs, that you can use if you want to make a basic user interface. For example, you can
use one as a power on/off button.
We bring out GPIO #23, #22, #21, and #18 to the four switch locations!