they seem all same to me.
That's because they are not that different from eachother
If you are beginning, there is little point in investing in an expensive Bose or other ANR set, which typically also require batteries.
As mentioned by rjtjrt, the basic David Clark has stood the test of time, are easily available and easily fixed if they ever should break - although you wouldn't expect them to.
Once you have gained your license, you can always offload it and upgrade - by then you will know what to look for, have tried on those used by your FI or buddies at the club etc. and will be in a better position to judge what you need/want.
You may also find that your school will have sets you can use/borrow/rent - in my neck of the woods they are almost certainly DCs.
Just to add to the confusion - personally, I use these
QT Halo in-ear headset.
B.