Shipping as eu resident to the us [taxes - worst enemy of humanity]

[MajkelJ]

Hello,
I'm located in the eu and I would like to start my dropshipping journey to the US. I plan to use cjdropshipping or usadrop as my supplier. The question is how do I pay the sales tax? Do i just include it in my product on shopify and that's all? Or are my suppliers already dealing with it as they are located in the US? And also is there any other tax in the US that I should be aware of?
Thanks in advance,
Majkel