In short, there is a 10 MB file size limit on our hosting which cannot be increased.
What to do with the 2-3 GB file depends on what the file is about. If it’s an archive with code for your website, please extract the folder on your own computer and upload the extracted folder with FileZilla. If it’s a file that should be available to download, please upload it to a file sharing site like Mega or Google Drive and just put a link to the download on your website instead.