Is there a way to create a panel with buttons etc. on bottom of screen that stays there even when i am moving/rotating camera in 3D world?
What do you mean by a panel of buttons? Do you just mean UI that floats over the scene? If so, you can just use a 2D Screen and put your buttons there. If this panel will exist in the world space, you could always use a 3D screen that is a child of the camera. Check out the Screen documentation here:
well I mean somthing similar to this panel
with buttons but it will be on its place all the time even if I rotate with the camera in 3D world
That use-case looks like you would want to use a 2D ScreenComponent with a combination of buttons and images to get the look and feel your aiming for. The 2D Screen renders on top of all of the 3D/World elements in the scene.
Check out this relevant part of the manual to get started:
edit: Provided example setup with 360 tutorial project in PM’s: