If you want mainly macro photos, there are lots of options.
This article covers some of the options on a DSLR. It is 4 1/2 years old, but still relevant.
and here is a similar write up from another fella https/photography.tutsplus.com/articles/a-poor-mans-guide-to-budget-macro-photography--photo-2857
A disproportionate percentage of people in to Macro, and especially "macro-hacks" favor Nikon cameras OR adapt Nikon Lenses to other bodies such as Pentax, Sony, etc. It is simpler to use Nikon lenses on Nikon bodies.
Nikon has been making cameras for a long time. The older ones can be had quite cheaply and so long as you take care to learn what you're doing they can still produce stunning results.
With your budget you might also be able to find a used bridge camera with a decent macro capability. What you want to look for is 1:1 or greater magnification. Many have this. You can check amazon.co.uk or Jessops for safe purchases.