Save download files mobile android chrome browser using just one long press. In mobile browser no option found for download files. Here option given for save download file and check downloaded files detail.
In mobile phone browser normal option list you found New tab, Bookmarks, History, Find in page etc option but no option found for save page image or any file in page.
For save download file in mobile android chrome browser just long press link, file, image (For mp3 song long press on play icon). After long press browser open new popup with extra option. Popup also includes save download file option.
Once file downloaded, you can find it from download manager, also you can check it in file manager.