how to post multiple photos from pc to IG?

can't figure this out, talking mainly about multiple pics in same post, I have an old phone where I keep my IG and can't transfer photos to it so I have to somehow make it from PC (4 pics in 1 post)

Install droid4x for virtual android on your PC
If you have a Mac, Flume works really well

I second FLume, it's fucking fantastic. You can DM! comment, like, post pictures, everything except watch stories. After recent API changes, Hootsuite is dead, PeopleMaps seems dead, so happy to find Flume. They also offer 25% commision on referals for $10 pro account (more than one account and yo need a pro license)