Best Dropshipping Method

I need some advice, I have been growing a few insta pages for different niches (food, soccer and health) I'd like to start creating a store for each individually niche so I can start selling some items.
Where do you guys recommend I look for my suppliers, all this is US based.
best, greengo

Wasnt able to replay normaly because of some spam alert, so i added my response in picture!