why cant i download any soundfonts?

so i was interested in downloading a sound font and found salamander piano v3 and i really liked it. i downloaded it and put in documents/ musescore/sound font. it didnt work. I noticed that the file is a bz2 file and have no idea how to change it to a sfz or sf2 file. is there some way i could do that?

p.s= i am not a programmer or anything so i have no idea what any of these means.