Not sure how much you know about ripping CDs, so apologies if you know this.
You can use Windows Media Player to rip a CD down to MP3 files. You can adjust the bitrate (quality) when you rip the CD.
Use the best rate you can to ensure the quality of the MP3 file is suitable. The usual advice is use the top rate available. In my (old) version of WMP the top value is 192.
You will then have a number of MP3 files. These should be organised into a folder. The folder hierarchy I have seen recommended is Artist>Album, so a folder called U2 will have a folder inside it called Joshua Tree, and that folder will have the MP3 files in it. You can add more Album folders into the U2 folder, or create a new folder for a different artist.
You will need a card reader plugged in to your computer or laptop (or this may be built in).
Insert the SD card (Max capacity 64Gb) into the card reader and then use Explorer to copy the U2 folder to the SD card.
Once the copy is complete, remove the card from your reader, insert in your car, and select Media in the MMI.
Select the relevant SD card, and your music, or whatever, will be displayed.
There are other threads on here which go into the format of the folder heirarchy in more detail.
I have Four top-level folders (Drama; Comedy: Music; Musicals). Under each of these are folders for Album, or Title (Drama & Comedy), or Show (Musicals)
So I have Comedy> Cabin Pressure> S1 and the individual episodes in the S1 folder. Works for me but you may prefer another structure.
There are instructions on how to navigate the folders through the MMI included with the car.
Note: Only picked U2 as it was less typing.