The flag is dedicated to Tsukamoto Ryōichi, and possibly sent from Asahara Kazuo (note the characters used in Japanese have multiple possible readings, so the readings could be different than what I've given above).
The rest are all names of the people who signed the flag.
The banner is also dedicated to the same person, Tsukamoto Ryōichi. It is a banner that says "Congratulations on Joining the Army". The banner is given by Uchida Takeshi of Tokyo.
The white cloth with the red embroidery on it is a classic "senninbari" (cloth of a thousand stitches). Its a kind of memento made by (usually) women to give to soldiers heading off to the front. The thousand stitches means each woman of the neighborhood or the school or factory or whatever, each makes one stitch. It has the stamp of a shrine, "Hachiman Shrine".
As always, there are many WW2 fakes out there simply because it is so easy to take a piece of cloth and make it look aged and add some writing to it. Cost is minimal, but you can sell it for a few hundred bucks on ebay, hence there are a million fakes. This one looks ok at first glance.