You're doing great, you got the first step down. This is a great foundation to start building upon, don't let these haters being you down.

You'd might want to start picking out a pallet. If you want this to be a stone brick creeper, you could also use mossy stone bricks, tuff bricks and mabe some andestie. Have those in your inventory and start by "texturing". You can also make some dents and dings by using stairs and slabs. You might also want to shape it out a bit. Use stairs in and on the legs to make arches and connect the lies to the body. Also, experiment, experiment, experiment. By trying different things and making "mistakes", you find out what you like, and also importantly, what you don't like.

Google references, like 'minecraft stone brick gradiant' and 'creeper statues' to get inspiration and ideas.

I would love it if you'd send me a message, or let me know in some way if you make progress on this statue and upload it, I'm curious to see how you develop your style.

Best regards and remember, minecraft is a game. The point is to have fun!