Can't Find Options to Reduce Photo Size on iMac
I am trying to reduce photo sizes of files on my iMac. Some are in Photos and some are in other folders. I looked at some of the answers on these forums and cannot find options to choose sizes for the destination photos. (El Capitan system). I tried Sharing and Export and see no options to reduce pixel size. Another frustration on using this system. I would have thought typing in photo size reduction in Photos Help would have helped me but once again Apple seems to be saying "that's for Apple to know and you to find out" . I know most you long time users will be able to address my question but my frustration with Apple App help continues to frustrate me.
Thanks in advance.
OS X Yosemite (10.10.4)