In a lithium-iodine cell, 2 atoms of Li are oxidized to 2 Li+ ions and l2 is reduced to 2 write the oxidation and reduction half-reactions that take place in this cell

I'm learning about the periodic tables and what each subject's configuration is. for example, hydrogen is 1s^1, but i don't understand how you get that. can someone me understand how to figure out how to figure this out? sorry if the question makes no sense, but it would really a lot if you could me understand! you so much if you can!