This is a rather broad question; difficult to answer.
In principle: joining data to shapefiles is an easy thing to do in the workflow of sf package - as the sf objects are data frames, so the usual tidyverse suspects such as inner_join() apply. Workflow based on the older sp package is somewhat more challenging, but still doable (if I remember correctly the trick was to link based on a key value instead of just position; but I have not used the sp workflow for some time).
The difficult part is getting hold of an appropriate shapefile, which I can not help you with as the question stands, as I do not know what region / administrative units your data applies to.
EDIT: a while back I have written a package with sf objects of shape objects for the Czech Republic, including administrative regions. Attaching census data and drawing a choropleth chart is the #1 example covered by its vignette - have look if wou wish
https://cran.r-project.org/web/packages/RCzechia/vignettes/vignette.html