Samsung

Not Long time ago i bought a Samsung earbuds+. i have samsung 8s+ but these "cute" earbuds are not working well with my mobile. The music sound is so low ! But when i connect with my hp laptop they working very well! Is this normal or maybe my earbud...

can someone tell me what i should do to make themes and sell in Galaxy store?

I would like to know how or where i can make themes, icons.... and sell them in "Samsung Themes"?