Is it possible to install the Eikon API Proxy on ubuntu/linux?
If not, is there any way to get data on ubuntu easily?
Refer to this question, the linux version will be addressed after the Beta period.
For your question, if you would like to get real-time data, you can try Elektron APIs. However, to use Elektron APIs, you need to have an access to Elektron data feed.
You can also contact your local TR's sales team or account team for more information.