You haven’t really given much detail about the site, or which pages you’re particularly interested in from a UX or design point of view, so I’ll just give some comments at random.
The contrast of the text on the background colour is poor, making it difficult to read. I have good vision; it would be inaccessible to somebody with poor vision. Your main navigation is keyboard-accessible, which is good, but there is no visual clue to indicate where I have tabbed to, whereas mouse users get an indication on hover.
I don’t speak Spanish, so can’t comment on the text which is there, but in many places there seems to me to be a shortage of text. For example, on “Inicio”, there is a series of unconnected images with no text to explain them, introduce them, or tell us anything about them. Elsewhere on the forums you have mentioned the difficulty of getting your site indexed by search engines. With no text, there is little that can be indexed.
On the “GalerĂa” pages, a number of the images link to empty categories, which gives the impression of an unfinished site.
Under “Tienda”, the photos have captions, which is good in theory, but in practice the captions tell us very little. (Bizarrely, the text here is in English. Is that because this is iframe content from another site?) Assuming you have control over this text, then use it to add something of value, I don’t know whether selling photos of the Harlem Globetrotters could land you in legal trouble, but leaving that aside, what does “Harlem Globetrotters match” tell us about the photo? Which match? When? Against whom? What is happening in the image? I note that you are also using identical text for both the alt text and title on these images. I suggest you read this page for guidance on writing good alt text. Using identical text in multiple places like this may also be interpreted as keyword-stuffing.
Again, as the “shop” area is from a third-party site I don’t know how much control you have over it, but I would prefer to see headings for each section, and a more logical arrangement. e.g. all sport-related images together. I know there are “collections” which can be accessed from the menu bar, but those links are not keyboard-accessible, and simply paging through the photos, it all feels quite random.
Your problem, as I see it, is that you are in a highly-competitive niche. There are large, well-established sites such as Pixabay, and if I were looking for, say, a yellow flower, I would go there first to search. You need to find some way to get your content to stand out. Tell us more about it. Where did you see that yellow flower (assuming you haven’t been able to identify it)? What made you want to photograph it? Were there any challenges, such as it being a windy day?
I’m sorry if this has come across as very negative. It’s not that there’s anything very wrong with the site (apart from accessibility issues), more that I feel it is lacking in character.