CS0246: The type or namespace name 'Sq|Connection' could not be found | But using SQLClient added

Can you help me to buy a coffee:
www.buymeacoff... CS0246: The type or namespace name 'Sq|Connection' could not be found (are you missing a using directive or an assembly reference?)
The name 'SQLConnection' does not exist in the current context

[@saif-s5r]

u r the best

[@renansia4]

thank you bro

[@muhammadhammadkhan9850]

thank u

[@Burak-vz6bf]

thnx

[@jojispoon3619]

help it still doesnt work bro