Open the sticker picker in any channel on ୨🌱୧ Chrysalism ꒦꒷ and pick C_hehe_cat.
Sending it on other servers or in DMs needs Discord Nitro.
To add it to a server you manage, download it, then open Server Settings → Stickers → Upload Sticker. Discord takes PNG, APNG and GIF files up to 512 KB.