Bad lens, as in Canon EF-S 18-55mm f/3.5~5.6: each shot has a massive flare in it. This lens shoots very poorly toward the sun, and at the wide-angle end, such as at 21mm in the shot of the kids, it has a lot of chromatic aberration in the images it shoots. This is a very low-cost "kit zoom" that cannot be shot "against the light" without high risk of flare. This is an issue with many zoom lenses: poor ability to shoot 'against the light' as most say.
Do you have a lack of resources? Yes, and no. For example, a really GOOD lens, like say a 35mm prime lens, with its own dedicated lens shade, could have shot these images, and not given that big flare spot, and could have created much higher image quality. The tiny little lens shade that comes with am 18-55mm kit zoom is sort of an afterthought, a marketing ploy. The hood is NOT optimal for all focal length settings; one,single hood can, in fact, NEVER be able to provide optimal shade from the sun; that is where single focal length lenses, and LONG, full-shading lens hoods come into play. To optimally make the 18-55 kit zoom work its best in this type of tough situaton, you need a lens shade solution that WORKS; meaning, something like an assistant with a clipboard or piece of black-painted cardboard throwing literally, a shadow, onto the front element of the lens. Or a compendium lens shade.
You know the orange-eared shot of the boy, in the other thread? That same strong sunlight, when it strikes the front element of a zoom lens, either directly, or at a glancing angle, can cause lens flare, or ghosting; your 18-55 lens created one, or two BIG, round flares. Not tiny, hard-to-see,little flare spots, but BIG flare spots. That's what I meant by bad lens....and it has terrific levels of chromatic aberration (color fringing is another common name for this optical defect) at the short end of its zoom range: this is VERY common with 18-55 lenses that cost $99. But-this is the issue: a photographer MUST be aware of lens flare, at all times. Lens flare is the ditch for the driver. The gopher hole to the pastured horse. The sniper to the common soldier.
Reflector, reflector stand or grip solution; ancillary lighting gear (flash units), lighting modifiers...these are lacking to some degree. Even one, single, medium-power speedlight flash could have made these family sessions better, by far, by creating better lighting in the field. Photography is a big, broad field, and there are a lot of things for you to learn. You really do not have the knowledge or ewuipment needed to make this "easy"; you're at a place right now with low-cost equipment, and NOT much of it, and not a lot of knowledge about the skills needed to shoot for money and not have the possibility for big errors to creep in. The first thing would be gaining knowledge. I'd suggest book-learning, or some of the links KMH has provided. AND, this is the thing...if you qant to be able to shoot toward the sun, or to shoot in strongly back-lighted situations, you need to get a lens that performs better than the 18-55 does, and that lens needs a fully-working lens shade on it, and an optical design that RESISTS sun-flaring to a high degree.
I do not want to discourage you. And neither do the majority of posters here. But there are a lot of things you need to learn how to do; theory, and practice, and also, equipment that many other people have, and use, for similar photo sessions. I started taking photos in 1975. There is plenty to learn. You can learn rapidly, or slowly.