Select the standard object like opportunity then create one opportunity,save it after that a page will display go to product section and select add product.
I have come to your website for the first time today and here I have get a lot of information, (https://hoozoelectronics.com/product/hm01/) thank you very much for this.
Regards
Khushi
If u find fruitful regarding your queries then marked my answer as solved so that others can also be benefitted
Thanks & Regards
Khushi