In the example below the default breaks were 1 month, but I overwrite them to make breaks every 2 weeks (which is counterintuitive for given data but shows the concept).
For your specific case use date_breaks = "1 day".
suppressMessages(library(tidyverse))
suppressMessages(library(lubridate))
df <- economics %>%
filter(date < ymd("1967-12-31"))
ggplot(df, aes(x = date,
y = pce))+
geom_col() +
# You can manipulate breaks in the following way
# Use set value "1 day" for breaks on each day
scale_x_date(date_breaks = "2 weeks")+
theme(axis.text.x = element_text(angle = 90))
