Creating a slideshow without using Powerpoint

You could even use Google Slides and download that onto your Mac/edit it using Keynote or Microsoft Powerpoint. Their layouts are easy to customize and work with so you won't be stuck using Microsoft Powerpoint's templates.

Keynote is Mac's version of Powerpoint; you could use that.

I'd be wary of using an online source if you've only got WiFi available. WiFi can conk out at the worst times. If you can plug an ethernet cable directly into the computer, that's better for online content.

I’m not sure about apple compatible, but amazon photos is really easy to use and a great way to keep albums safe.

I've heard great things about Slydely!

I believe you could use Prezi.com!

It's better than power point IMO, and after you finish up you can access it on any computer because it's a website, but can also download it and save it to a USB (I believe).