You can certainly post them, as long as they are marked casual.
Some people use iNat to document their gardens, and post observations of cultivated plants, and like zoo animals these become Casual not Research Grade, and that is widely considered acceptable.
To reach other photographers, you could use Flickr, which is primarily a photography site. An account is free for up to 1000 photos. There are many photographers on it who specialize in animals. You could connect with some of them, and find a community there.
https://www.flickr.com/photos
And do stay on iNat, too! Sometimes in Forum topics people give excellent photography tips.
These Forum topics have some great photos:
https://forum.inaturalist.org/t/what-is-your-favorite-lifer-from-this-week/24219
https://forum.inaturalist.org/t/best-photos-youve-uploaded-on-inat/45317
There’s no requirement that your observation has to be Research Grade to share with us there!
And finally, this topic is where we courageously share our worst photos:
https://forum.inaturalist.org/t/whats-the-worst-pic-you-uploaded-to-inat/40286