Newbie needs recommendation for fast learning a little php.

I don't even know if I'm up to the level of being a newbie at this
point. I mostly need to do a specific thing, get a html file to
display its last modified date and time inside itself.

I'm not sure a book is going to be that useful, but maybe a Web site
could be. I'd need one that really is basic.

I've found a Web page or two, but they seem to assume that I know more
than I do because I can't get the code snippets I've found on those
Web pages to work.

I used to use ssi for this, but I moved to a new Web host and they
seem to have their server time zone set as the only time zone I can
display, and they are far away from me, so in ssi I get a date and
time for a file modification time that's many hours off. I'm hoping
that php will solve my problem. Thanks in advance.