Where do I suggest new emojis?

you can suggest it to the international unicode org

Guidelines for Submitting Unicode® Emoji Proposals

it's them not apple who handle the emojis

I don't think Apple creates emojis.

If you have some suggestions or proposals then you are free to provide them here --> https://unicode.org/emoji/proposals.html

no, for emojies to be multiple platform rather than apple devices only the international unicode org handle it

if you want to know more Unicode - Wikipedia