Bagster
Bagster
Er, do you mean emojis?
They are on my DS iPad and my explosive Note7, but my desktop is for the serious business of making money, so...I will look tonight when I get home and advise.
Of course -- that's where almost all of them were made. But that doesn't solve your problem. If you're talking about emojis (e.g, yellow happy/sad faces), those are funneled through a standards organization, so that MacOS, Windows, iOS, Android, and Linux share the identity of a given emoji code. Though the precise look of a happy face may differ between platforms, the computer code for happy face should display a happy face on every platform Emojis are only created by the platform vendors. Instructions for choosing an emoji are here.
If you're talking about things like the red Q pill you use as part of your signature, there are ways for users to create them. The common but expensive tools for this are Adobe Photoshop and Adobe Illustrator. Photoshop is excellent for photos. For example, if you found an image of a red pill on the internet, you could erase its background, produce a shadow effect, superimpose text on it -- as TXnMA (was it?) did. Illustrator, a graphics editor, would allow you to create such a pill from scratch.
Both of these tools are pretty expensive, however. Fortunately there are free tools that come pretty close. For photo editing, GIMP is a pretty good approximation to Photoshop. Although I haven't really used it myself, Inkscape appears to be a pretty good graphics editor. Both of these are free.
After all that, what did you have in mind?