I’ve bought some beanies off Amazon and so far these are my favorites in terms of fit, quality and style. They’re both “slouchy” beanies which is what I’m into. It’s also worth noting I have a pretty small head, so they could fit differently on yours if you don’t. Hope this helps!

Slouchy Beanie for Men & Women by King & Fifth | Premium Quality Beanie Hat + Warm Winter Hat + Charcoal Beige Beanie https://www.amazon.com/dp/B07X1ZG66F/ref=cm_sw_r_cp_api_i_uZjuEbCJZ4YS2

My go-to beanie. Comes in different colors, but I’ve found they differ in size so YMMV.

KBW-12 WHT Solid Slouchy Beanie Skull Cap Hat https://www.amazon.com/dp/B00NB9CKE6/ref=cm_sw_r_cp_api_i_.3juEbRQJXS41

Tons of color options with this one.