Cows

I think you need to work on some basics first. This will all be my opinion and yours can be different and I dont want you to tell how to do stuff so this would be how I would do it.

Really the cows wont move much, so you can afford to go slow shutter and low ISO, looks like you got quite some ISO noise in there.

Fstop: Try to open your aperture as open as possible, gives you more depth in the image and also more light for less ISO

Digital Zoom/ crop: Did you use any heavy corp or digital zoom on this? Try to avoid this since it will degrade your image quality a lot especially on a lower end camera.
Either get closer to your subject or get a longer lens to achieve your framing as much as possible in camera.

Framing: If possible I would not frame the cow dead center only if you are really close, also I would go lower to get a more pleasing image. I think the first image is the strongest one, but in general be aware of your background so you dont just have a fence there which is not very pleasing in my opinion.

Lighting: Having flat light except for the first image is very hard to deal with and get good results. For a simple start I would recommend getting the sun in your back and shooting with the sun to your subject, which will allow you to get better lighting and an overall more pleasing image, once you master basic lighting you can try back light or something else what you want to try.

I think you can improve quite a lot of things here but on the other hand dont try to handle everything at once. Maybe go out for a few days only looking at lighting or only looking at framing and so on so you can improve in those areas. Once you know your stuff you can begin to get everything in one picture.
Hope I can help and keep shooting.