That is a tall order..
I doubt you will find one VST that has a whole symphony-orchestra of high quality. You will have to get many VSTs with different instruments, and kind of asample your own symphony-orchestra.
Then again i have to mention Synth1.
The reason is that there are so many free pathes and banks, and many of them are violin woodwind and brass-instruments. You may find something there.
Ofcause 'we' can also just 'do a google' and first up is
https://thehomerecordings.com/free-orchestral-vst/