I know there are tons of tutorials online, but when I get home I could remember how to resize in FireAlpaca, without it in front of me I'm useless... XD
But I think you need an add-on for FA to make gifs, you can always just save 2 pictures of the same size, one open eyes, one shut, and use a gif making site, you just put in your images and they compile them into a gif for you. =D
Hope this is somewhat helpful.
I'm kind of new to FA as well, but I've gotten to know it pretty well so lmk if you need help with anything! ^u^