Help upgrading my pc

Hi! I posted a while ago about my new pc and I got tons of great advice! I’m finally ready to upgrade it, but I just want to to make sure that I don’t screw anything up. First, I was recommended to get a GT1030, but there’s a bunch of different options on Amazon and I’m not sure which one to get. I don’t want to get the wrong one that’s not compatible. There’s this one and this one and also this one I’m not sure which one is the best to use and if it will even fit into my case.

I’m also planning on getting this set of ram, hopefully this is fine. The pc I’m using is the one I got for Christmas and if anyone could recommend a good monitor that’d be amazing!! Thanks for any help. Sorry for all the links, just learned how to do it