Hello, as the other person said in his comment, just type 915 tkl key caps on Google and sites of Chinese origin offer all sorts of keys adapted to this keyboard at OK prices, for my part I found replacements for less than 10.-.
By the manufacturer's number, which can then be searched for here: https://www.logitechg.com/de-ch/products/gaming-keyboards/g915-tkl-wireless.920-009498.html
So these are tactile switches.
This game is not originally intended to be played with a keyboard/mouse, but after some research I was able to find these tips for using a keyboard/mouse for Xbox:
"The best option would be the Logitech MK270 wireless gaming keyboard and mouse combo, and those who aren't too budget conscious should consider the Razer turret or Logitech G613 wireless keyboard and G603 Lightspeed wireless mouse."
Otherwise there are controllers designed for flight simulation like this one compatible with the Xbox https://www.digitec.ch/fr/s1/product/hori-hori-flightstick-ace-combat-7-manettes-12858767?supplier=406802
This product is equipped with GL touch switches. We do not sell it with other types of switches. This is a CH keyboard (qwertz, with accents: é, à and è).
The keyboard has a Swiss ISO layout, i.e. the arrow keys next to the shift key are present. The second picture shows a US layout. However, pictures are not binding on Digitec, what counts are the specifications.
Unfortunately, we do not have any information on this yet. As soon as the product becomes available for us through our suppliers, we can check a possible inclusion.