how do I obtain my photo file and get the 64-bit app that replaces iPhoto?

My iPhoto library was appearing as a Photos library. I tried simply clicking on my iPhoto library and the computer asked if I wanted to open it in Photos. So I replied affirmatively, and it began another hour-long process of updating. Now my photos are finally appearing in the Photos app, for which I am very thankful.

At the bottom of the screen is a new task bar which has me a little worried, after everything else I’ve experienced these last few days. Under the blue bar (which is about 15% completed) it says “leave device connected to power.” And above the blue bar, it says things like Analyzing Scenes and Gathering Favorites and Composing Layouts. I just hope the MacBook doesn’t crash again after whatever it’s doing.

thanks all for your advice

I followed the advice. The computer took many hours appearing to move my iPhoto library to the newer Photos location. But when it achieved 100% completion, a dialog box appeared saying that Photos was not able to open my iPhoto file. I tried to do it again, and the computer is now saying that everything from my iPhoto has been migrated to Photos. However, when I open Photos, there is nothing there. I tried a restart, and the computer took painstakingly long to restart, and it gave me a message that my computer had to restart "because of a problem." After restart, I still have nothing in my Photos.