I couldn't make a number line but I will just <em><u>explain</u></em> how to do it.
draw a <u>number line</u>
write <u>0 - 20</u> on it (or honestly whatever numbers you want, depending on how big you want your number line and if you want to include negative numbers on it)
<u>find number 12</u> and circle it
then <u>count up 7 </u>(so 13, 14, 15, 16, 17, 18 , 19.)
then you can <u>circle 19.</u>
this is optional but you can draw a rounded arrow from 12 to 19 and write +7 on it to explain that you added 7
I hope you get this right, wish you luck! I worked hard on my explanation lol