download either Sublime text 2 (i prefer it because if you ctrl click on a different line or somewhere else you can type on multiple lines at once) it also has a minimap for all your code
http://www.sublimetext.com/2



Java code for an old mod, but i still use eclipse
sublime text master race

or notepad++
https://notepad-plus-plus.org/download/v6.8.3.html

and how I can open the .json textures?

you open the 1.8 jar and copy the resources folder into a new folder in the resourcepacks folder and get a pack.png and pack.mcmeta, or it wont show up, what i did is i took one from a texturepack and edited the file completely, as a template

brb thanks, for the sounds how I can make or put them into the pack?

And where I can get the mc 1.8 textures to make my pack?

id say gimp first then paint.net spoopy linked it and gimp http://www.gimp.org/ i overall prefer gimp for the pencil tool that locks itself to drawing onto pixels instead of having to zoom in 8000% to be precise only need to zoom at least 1100% for 32x32, and 16x16 800% for 64x64 and anywhere in between for 128x-512x gets harder with higher resolutions because you need to keep track of the pixels

GIMP is a free program and is relatively good for pixel art.