Let me see if I can help.
1 . Uploading a gif to steemit is fairly simple. You just need the link to where the gif is already on the internet. for example, I use "giphy", on the website, you can select to "share gif". Where it says "gif link" you want to highlight the contents of that box. Cutting that and pasting it into a steemit post will show the desired gif.
For example

h ttps://media.giphy.com/media/3oz8xSOxnqbONxOCoU/giphy.gif
(I broke up the web address by putting a space in between the "h" and "t" of "https" so you could see it)