Advice for posting to Insta?

So I have a heap of photos from motorsports rallies that I'd like to post, but in terms of cropping, all my photos are zoomed in horiztonal that don't allow for much 4x5 cropping. Is there a way I can crop my photos for maxium screen usage on phones while still getting most of the shot?

Not doing this for following, just want to have an account to upload to as a end point I guess..

Thanks