Hello! How can I use these sounds in World Editor?

First, you have to replace an existing soundset with it, because WC3 doesn't have a way to create a whole new one. Here's the steps:
• Choose a soundset to replace with this one. You'll need to replace individual voicelines, so pick one with the right amount of voicelines. For example, for this one you want to replace a soundset that has 4 Pissed lines, 3 What lines, 4 Yes lines, 5 YesAttack lines, plus a Warcry and a Ready.

• Rename the custom soundset lines in your files to be identical to the ones you want to replace. If you wanted to replace, say Arthas with this one, you'd change the name "BalnazzarWhat1" to "ArthasWhat1"

• Right click the voiceline you want to replace with a custom one, and choose "Replace Internal Sound." This will open your files, so find the folder with the custom soundset.

• Double click the voiceline you want to use in place of the one you are replacing.

• Repeat with the other voicelines until you're all done!

PS, if you have too many custom voicelines and not enough on the existing soundset, you can pick and choose which ones to use and which to not. If you have too few custom voicelines on the other hand, you could re-use one or two custom ones; for example, if you have three custom What lines, but the existing soundset has four What lines, you could use the custom What1 for the existing What1 AND What4.
Hope that clears it up! If you have any other questions, ask me!