Aurora R11, possible upgrades

The easiest upgrades are the RAM and disk drives.   Other upgrades are harder, but possible, due to the small size case of the R11/R10/R12 and proprietary parts used by Dell.   So, things like fans (to cut down on the noise and add a small temperature benefit depending upon how you do it) can be upgraded and some specific 3070/3080 GPUs will fit but not most due to the small case size (280mm max card length).

For RAM upgrades, search here and on Reddit, as Dell OEM RAM is proprietary and won't play nice with aftermarket sticks and they don't tell you that upfront....so your best bet is to buy brand new RAM so it's matched sticks and then it's plug in no problem.  Lots of posts here on the types people have bought and the spec (size, # of sticks, CL latency, overall speed, etc).   

As for disk drives, those are easy and the R11 already has the power connector wires inside the case, so all you need to do it buy the 2.5" drives you want and the SATA cables and it's an easy install in the 2 slots in the bottom of the case.

Ask yourself first while you want to upgrade. Less noise, more performance, drive to slow, CPU throttling, etc...?

Unless you are experiencing any issues, you specs are pretty good right now.  Now is not a good time to upgrade a GPU, they are out of stock everywhere except for scalpers at 2 to 4x msrp.