nah, concerts are different from that. a concert is some hour+ long event where only one group is present, each of the members has their own solo and they play songs from their entire discography, including b-sides. gfriend had a concert recently i believe, although i don't follow them.
what you're seeing from momoland is them promoting/performing boom boom at shows, high school opening/graduation ceremonies and other different venues like malls.
go to youtube, type "momoland nancy fancam", click on a few of the results and you can see in the video descriptions where the performance was held and what the occasion was. for example>180322 낸시 Nancy 모모랜드 MOMOLAND '뿜뿜 BBoom BBoom' @Wonkwang University Freshmen orientation