Ubuntu in virtual box bad performance (graphics)

Hello everyone,
as windows-user, I tried Linux in the last 20 years serveral times. The result was always the same, I didn't get simple things managed. Now I have to use Linux on my job and tried to run it on my private notebook also. I installed Oracle virtual box and some linux distributions:
- raspberry OS
- Lubuntu focal fosa
- Xbuntu focal fosa

In every case I have no graphic performance. I'm not able to watch a video. It doesn't matter if it's from my mobile self-recorded or from youtube.

My idea was, I have a problem with virtual box. So I installed Budgie (focal fosa) on an USB-stick and booted from there. Same Problem, and the all-around performance is maybe also a little bit lower.

I was running a website called speed-battle, I don't know if the results are accurate. It shows a not very good performance of my notebook in windows-mode. With vm+linux it's round about 55 %.

My job-notebook is more high-priced. I ran the same test. Windows performance was good, vm+linux was 20 %. As slow as my private-notebook with linux. And also with this notebook I am not able to play videos.

As setting I used: VMSVGA, 128 MB graphic memory + 3D-acceleration (I don't know, if that's the correct word in english)

What am I doing wrong?
sincerely yours