水分補給 literally means to supply water, referring to the process of hydration.
パスワード means password. USBメモリ means a USB flash drive. An employee lost a USB flash drive that contains personal information of over 460 thousand people of the city of Amagasaki recently.
年収200万 means an annual income of 2,000,000 Japanese yen (roughly 15,000 USD). There's a magazine titled 「年収200万円で豊かにくらす」, that is "Live Richly with a 2 Million Yen Annual Income".
博衣こより, or Hakui Koyori, is a vtuber of the agency Hololive Production. On June 16, she streamed in 3D.
和菓子の日 means the Wagashi Day, a day to enjoy the deliciousness of wagashi (Japanese dessert) and to pray for health.