I use the bupaR package to create a process map like below
library(bupaR)
patients %>%
process_map(performance(mean, "days"))
perf<-patients %>%
process_map(performance(mean, "days"))
what I would like to do now it to extract the data from, to and value as I can see them from the object that is created and pass them to a dataframe.

Maybe
edges <- attr(perf, "edges"). This will give you a tibble from which you can extract the columns, runhead(edges)to see them.