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The answer is yes, but you'll need a sourceport to use them. There are two very good sourceports of the Q3 engine: ioQuake3 (https://ioquake3.org) and Q3 Spearmint (https://www.moddb.com/mods/ioquake-iii-arena-4k, basically Spearmint is based on ioQuake3 and that's the reason why the website says that it's ioQuake 3, the package really contains Spearmint). If you want to play online, I suggest to use ioQuake3 along with some new and shiny icons (https://www.moddb.com/mods/high-quality-quake) and textures (https://ioquake3.org/extras/replacement_content/). Q3 Spearmint has even more improvements (better widescreen support for example), but it's intended for single player gaming mostly.

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Just use the package from the link above (https://www.moddb.com/mods/ioquake-iii-arena-4k). You don't need anything more. :) There's no need to be afraid. I used this package a few weeks ago and everything runs smoothly.

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Unpack the 4KQ.1.rar file and then unpack the spearmint-1.0.1-windows.zip file to a separate folder. To play Spearmint Quake 3, copy Quake 3's baseq3/pak[0-8].pk3 into the local baseq3 directory inside the unpacked Spearmint folder. To play the Team Arena expansion, copy Quake 3 Team Arena's missionpack/pak[0-3].pk3 into the local missionpack directory inside the unpacked Spearmint folder. Now copy the folders baseq3 and missionpack from the unpacked 4KQ.1.rar to the Spearmint folder. And you're ready to go. :) Just launch the spearmint_x86_64.exe file.

Your welcome. :) Have a nice time playing this wonderful classic!