Erreur dans yaml::yaml.load(..., eval.expr = TRUE) :
Scanner error: mapping values are not allowed in this context at line 2, column 8
Appels : ... parse_yaml_front_matter -> yaml_load ->
Exécution arrêtée
can you format the first part of your rmarkdown document (the yaml and the first few lines of the text) in the way it as was done by @DavoWW ?
You can do that by enclosing it with four backticks (````).
In that way we can have a good look at your code.
Now it looks like you did not use indentation which almost certainly is not what you did.