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Start out with a digital camera like this one - Nikon D3100 Digital SLR Camera with 18-55mm NIKKOR VR Lens. You can see the details at
http/www.bhphotovideo.com/c/product/730210-REG/Nikon_25472_D3100_Digital_SLR_Camera.html
B&H Photo is a great online store to buy electronics; very similar to Newegg, and I am a B&H customer for over 25 years and recommend them. Local stores such as Best Buy, Walmart, Sam's Cluc, Costco, are just as good but maybe priced a little higher.
After you start out with the Nikon D3100 and get familiar with Manual settings as well as Automatic settings, look into a "Macro lens". A Macro lens is what you really need for close-up photography of items like jewelry, stamps, collectibles, etc. - This Nikon 40mm f/2.8G AF-S DX Micro-Nikkor Lens will serve your needs -
http/www.bhphotovideo.com/c/product/810414-USA/Nikon_2200_40_mm_f_2_8G_AF_S.html
When you use a Macro lens a rigid tripod is highly recommended.
For online camera purchases make sure you buy "USA" and not "Imported" - Imported means that the product is from the "Grey Market" and does not have warranties and therefore will be cheaper. I do not recommend 'Imported'.