best way is gold chest. You can get plenty of them

Dungeon 17-6 itachi fragments. Unfortunatelly, rare

Train your kakashi to commender kakashi. Train your kabuto to bronze. Replace hinata with bronze obito. Put wrath 4 cursed seal on kakashi and kabut, wrath 3 on sakura. Summoning slug skill on sakura and no active skill. Place kakashi to first row. Kabuto and sakura on back row.

or shop

He gains bloodlines after you train him to bronze

He gains sage art snake and reincarnation. But the skill you are talking about needs 90 level kabuto. Even if you have bloodlines. You can't get enough amount till 90 level. I am also working on that

After you learnt them, you have to add "bloodline" to your hero for skill. Of you add necessery bloodline for skill , you can add this skill to your hero

!