Filling a combobox

Question

Hello! 

I'm just started learning c#, ado.net, and i need your help :)

I want to filter datagridview using combobox, but  i don't know how to fill my combobox from database.  I know that i must use DataSource, DisplayMember and ValueMember. I know, that i must create DataTable, and i must use DataAdapter.... but i don't know, how to use them. 

Help me, please))) 

I would be grateful!!