I recommend you look at product photography tutorials on youtube. You will need a flash as a minimum to achieve product photography indoors. A speedlite will do nicely, inexpensive and you can swivel the flash head around so you can bounce the light off a ceiling for example. A softbox on the flash will diffuse the light and spread it more evenly.
Im not a product photographer so cant give you the advice you would need to improve the pic, but I can tell you whats wrong with it.
Please, please do not take this to heart, its not meant to be hurtful comments, just observations ok
The jewellery is underexposed. Im not getting any "bling" coming from it.
The reflection of the jewellery, although looks ok, wont add to the jewellery, it'll just show you have a nice shiny clean table. The "bits" on the table, are very distracting and wont add nothing to the product.
The image doesnt look straight. But it might be because the jewellery isnt centred, its slightly to the left of centre. Thats easily solved, a bit of cropping.
The image looks quite noisy, hence you need a flash, the ISO can be dropped then, giving a cleaner image.
A tripod will help steady the camera and give you best focus as it wont be moving.
The image, wouldnt want me to "want" the product im afraid - as it is.
However, PLEASE go read some tutorials, get the equipment you need and add to this thread. Will be fantastic to watch this improve.