where can I increase the size of an image to upload?

for the size in MB I solved so:
[file your-file limit:10240kb filetypes:gif|png|jpg|jpeg]

I tried it with a photo of 1,79MB 4272x2848px and is successful

instead

I tried it with a photo of 2.85 MB 4272x2848px and it always fails!
the message error is this: “There was an error while loading the file.”

how to solved?

the message error is this: “There was an error while loading the file.”

Is this exactly the message what you see? Have you changed the message from the default one?

translate italian to english but the message is this!

Tell us the original Italian message, please.

Si è verificato un errore durante il caricamento del file.

OK. Read this and review your PHP configuration settings.

https://php.net/manual/en/features.file-upload.common-pitfalls.php