Can I separate the display glass from the display?

this is technically impossible unless you have vacuum chamber which would fit the screen. LCD is glued directly to the glass. even if you somehow safely separate it, you wont be able to glue it on new screen without air bubbles which could only be removed by vacuum.
use UV glue to reduce visible cracks. FT-12 (search for ft-12 iphone glue on aliexpress) masks minor cracks and makes them almost invisible. keep it aways from skin/eyes.

It’s a messy job! Apple uses double stick foam to adhere the LCD panel to the cover glass.

So you need to be very careful taking the LCD panel off with all of the other components as any bending of the panel will damage it (micro fractures) and you need to clean the adhesive off without getting the viewable area sticky or wet as that will stain it.

I truely don’t recommend trying to do this if you haven’t done a few before as it’s also a bit of a skill.

While it’s is more costly, I would just replace the full assembly.