This reproducible example shows one way to do it.
Note: For future posts please make your questions providing a reproducible example like this one
SinglePatient <- data.frame(stringsAsFactors=FALSE,
Patient = c(7212, 7212, 7212, 7212, 7212),
Session = c("post", "post", "post", "post", "post"),
Stimulus = c("blue_color.jpg", "brown_color.jpg", "blue_color.jpg",
"brown_color.jpg", "blue_color.jpg"),
Trial = c(14, 6, 19, 23, 18),
Running.Trial. = c("Center2ExpTrialList", "Center2ExpTrialList",
"Center2ExpTrialList", "Center2ExpTrialList",
"Center2ExpTrialList"),
Block = c(2, 2, 2, 12, 2),
ACC = c("incorrect", "correct", "correct", "correct", "correct"),
Side = c("L", "R", "L", "R", "L"),
Condition = c("Center2Exp", "Center2Exp", "Center2Exp", "Center2Exp",
"Center2Exp"),
Group = c("BrainHQ", "BrainHQ", "BrainHQ", "BrainHQ", "BrainHQ"),
new.RT = c(251, 253, 256, 261, 267)
)
library(tidyverse)
SinglePatient %>%
group_by(Condition) %>%
count(ACC) %>%
mutate(prop = n/sum(n)) %>%
ggplot(aes(x = Condition, y = prop)) +
geom_col(aes(fill = ACC), position = "dodge") +
geom_text(aes(label = scales::percent(prop),
y = prop,
group = ACC),
position = position_dodge(width = 0.9),
vjust = 1.5)

Created on 2019-07-22 by the reprex package (v0.3.0.9000)