hey jay! it took me forever to start trying blends bc i always found them so hard, so awesome for trying one so quickly!
first off, def check out those tutorials that rod linked to. tutorials saved my life when i first started making graphics and continue to save me when i'm in a rut
i also agree about fixing up that blending for the model on the right. also, it looks like the center model has been stretched a little bit vertically. make sure that when you manually resize/transform any image, you hold down the shift key because that makes sure the proportions remain constrained. also, check out websites like hq-pictures.com or hqdiesel.net for high quality photos of models/celebrities to use for your graphics. it makes them easier to blend and resize without losing any quality/causing too much pixellation.
first off i would suggest moving the images closer together. what do you want the focal point to be? usually, the smallest image looks best in the foreground. however, there are ways to play with that too depending on what you're going for. for example in this+ blend of mine, there's a small Elle behind the bigger Elle kind of mixed in behind the stock. i find that the easiest way to create depth is to layer stock/model/stock/model (or texture/model/texture/model). i also like to mix models in with text a lot to help flow & focal point like here+ (that blend is a hot mess with all the models but i'm just showing it as an example of the model interacting with the text).
what i would say is that here you have just a bit of a base. experiment by adding textures or .pngs. my go-to textures tend to come from RavenOrlov+ and LilithDemoness+ at deviantart. lilith also has great .png packs as well. (if you use their resources for anything in your gallery don't forget to credit!)
if you have an idea of what you want your text to say, then start to play around with it. however, if you're not there yet, start by layering models/textures/stock/.pngs whatever it may be. there's not so much on your canvas yet, so i think putting things on and playing around is your best bet right now.
when you've got some edits or new versions of the blend, post it/them back here in the thread and i/others can take a look
lmk if you have questions sometimes my writing is confusing lol