It's possible to create in free edition an dropdown(combobox) with brands?
And when select an brand to display all product from that brand?
also, for an certain brand, is possible to createa an custom page?For example for brand A i want page to be red and for brand B page to be blue
What you need is the "Filters", you can apply filters on the brands, and onclick it show the brands products. But it's available in the Business version of HikaShop.
For the custom pages, I think that it can be done by a edition of the view "product / listing_div", add a class suffix depending on the brands name or id and change the css properties depending of this brand.
You can adjust it in css, check which class is to edit (using FireBug for example) and then in HikaShop > Configuration > Display edit the frontend css file.
And apply a "margin-left" on this class.