Webscraping with R

I'm trying to create a script to download xlsx files from a website. The code below already downloads a file, but I need to change a specific parameter on the website by clicking a button.
When I log into the website using a browser the parameter is set to 176 (setIdPlantaAtual(176)), so the downloaded file corresponds to information from source 176.
What I need to do is to change this parameter simulating a button click to set this parameter to a different source.
Example: onclick="setIdPlantaAtual(275)". This is part of website's HTML.

What should I do to make this work?


url <- "https://genericwebsite.com/auth/login?redirectUrl="
download_url <- "https://genericwebsite.com/petpro/pets/generaterexcel.xlsx"
session <- html_session(url)
form <- html_form(session)[[1]]

filled_form <- set_values(form,
                          email = "myemail@myemail.com"
                          senha = "mypassword")

## Save main page url
main_page <- submit_form(session, filled_form)

#after login and submit_form do this:
download <- jump_to(main_page, download_url)

# write file to current working directory
writeBin(download$response$content, basename(download_url))

Can you provide an example that doesn't require authentication to fix the regexp?