Problem increasing maximum upload file size

Hi hoping someone can assist.
So I'm attempting to increase the maximum upload file size.

I believe I'm suppose to create a note pad doc php.ini with the following code:

upload_max_filesize = 200M
post_max_size = 200M

And then place in the admin folder.

I've done so but size doesn't seem to increase.
Any suggestions?

Thank you so very much for any assistance.

Mark