I'll start you with my best guesses, and others can let us know where I'm off base, or fill in what I can't tell you.
I believe "697 Med Coll Co" would be 697th Medical Collection Company, and that this would have been his unit. "Sep" is probably "separate", indicating they were not permanantly part of a larger organization, but would customarily have been attached for duty.
"C of G AR 615-365 & Sec II WD Cir 370, 44 (*)." is standard stuff found on many/most WWII discharges. "C of G" is convenience of the government and the rest of it is the regulation/directives which cite authority for same. I'm quite sure AR 615-365 is Army Regulation 615-365. "WD Cir 370, 44", is probably War Dept Circulation 370 of 1944, or some such.
I'm not quite sure about that under "Remarks". I believe, "ASFTC, Cp Berkeley, Tex." may be Army Service Forces Training Center, Camp Berkeley, Texas.
As I indicated, perhaps others will be able to clarify/expand on some of this.