To be able to play 24-bit files, the following is required:
1. A storage location
2. A player and software that can handle the files
3. Under certain circumstances a digital-to-analog converter
4. A good amplifier and speakers (or headphones) are recommended
If you manage many digital music files and listen via your stereo system, you should ideally set up a network hard drive which your player can access.
If you want to play the files directly on a PC/Mac, you can save the files there.
For streaming devices and AV receivers, external USB hard drives can be used which ideally need no additional power supply.
In general, a standard PC or MAC with appropriate software (JRiver, iTunes, VLC Media Player, etc.) is sufficient. You can also use designated network players, more and more of which can now be controlled by smartphone apps. Other models have their own remote controls. These generally serve as a D/A converter so you can skip point 3.
Of course, you can use an AV receiver, which completely covers the points 2-4. Or special mobile players that are optimized for 24-bit files.
The D/A converter in standard PCs and Macs are not sufficient. When used as a player, you should connect them digitally (e.g. optically or by HDMI) to a D/A converter or directly to an AV receiver with a D/A converter.
Amplifiers and speakers
If you have an "old" analogue amplifier at home, you must also use a D/A converter between the player and the amplifier. This can be integrated in the player, or an external device.