2 Qestions... 1 how do u make potions, 2 how do u collect the rain wate…

2 Qestions...
1 how do u make potions,
2 how do u collect the rain water and the sea water? i know you can only use rain water when its raining but HOW do u collect it. this may be a stupid ? but i can figure it out. please let me know if u can help me thanks!!