Just to make sure you like Roon and want to keep it, I suggest you install the Roon core on your Windows 10 or Apple computer. I am currently running the Roon core on my Dell XPS 15 laptop and it works perfectly.
Roon recommends that both your Roon core device and Roon end-point device be connected to your network using an ethernet connection. However, WIFI might work OK depending on your signal strength. I had an ethernet cable pulled to my Oppo 203 just to make sure I had the best possible situation.
You also need a device to control the Roon program and choose your music, etc. You can use a computer, iPad, iPhone, or Android device. Just download and install the app for your device. If you install the Roon core on your computer and want to use it as your control device, you do not need to install any additional sofware or apps.
Of course, you will need speakers or a soundbar, etc. connected to your Oppo for sound output. You can connect speakers using analog RCA outs or you can connect a receiver using HDMI, etc. I have my Bose soundbar connected using HDMI. To take advantage of your Oppo internal DAC, you would want to use an analog connection. If you use HDMI, you bypass the Oppo DAC and use the DAC of the connected receiver or powered speakers, etc, which may not be as good as your Oppo DAC