I Can use texture packs ?

It depends on the texture pack. The pack cannot give a runner a visual advantage (e.g. SpeedrunLegend's infamous run that used a texture to darken the nether brick block, making it easier to spot.) Ones that are allowed typically change the names of items or have similar coloring to that of the regular textures. I don't know which are legal, so either someone who responds after me will know or you can probably contact a mod.

You can read detailed rules on texture packs at http://bombch.us/DOOK. If you're not sure, err on the side of caution and open a thread in the java speedrunning discord. xqcL

se puede usar texturepack en speedrun?