As previously announced, two-time Grammy winners Kool & the Gang will bring their R&B, funk, soul, and disco hits to Tanglewood audiences for the first time on Sunday, June 23 at 2 p.m. Releasing 26 studio albums since forming in 1969, the group has earned seven American Music Awards and 31 gold and platinum records. Joining them are the R&B/soul trio En Vogue, who headlined last summer’s July Fourth Boston Pops Fireworks Spectacular with original members Cindy Herron and Terry Ellis alongside Rhona Bennett.