What are some best storage devices?

[Miagracelevi]

Hi everyone
I want to know that what are some good storage devices for my laptop. My laptop is running slow I think I need to save my all files in an external hard drive to make my laptop more efficient. My laptop model is FX505GE-BQ159T/GAMING VOUCHER - ASUS TUF Gaming . Kindly suggest me storage devices for mentioned model number.

 

[Why_Me]

SATA SSD.