Can you help me

I have an Oxygen 61 M-AUDIO and Cubase 10.5, but can not find instruments, and lack an asio driver. I’m a noob for this.

You need a driver for M-Audio Oxygen 61

See here. depends if yours is silver or blue model. Install driver then your computer should see it.
https://www.m-audio.com/support/drivers-search

For Asio download asio4all
http://www.asio4all.org/

Hope this solves your problem

Thanks for your post, at its did not solved my problem. Its seem that the “windows G5 wavetable synth” are inactive?

I installed Asio4all An thats work, but still have problems with instrument, how do it solved this problem?

Which VST Instrument are you using with your midi controller?