Loading library and creating date

library(leaflet)

a<-timestamp()
## ##------ Sun Sep  5 11:56:43 2021 ------##
b<-"Creadted at"
c<-paste(b, a)
c
## [1] "Creadted at ##------ Sun Sep  5 11:56:43 2021 ------##"

Making map using leaflet

map<- leaflet() %>% addTiles () %>% addMarkers( lat = 42.37033, lng = -71.09360,
                                                popup = c)

map