Display numbers in different columns per row

Hi, I have a problem hoping to get your help! 

I have a table (table a) showing how many children are in a certain program, with rows being counties and columns being different months from 2021-2023. I want to create a chart showing how the numbers of children in that program changed throughout the years (filter different counties). 

My thought is X-axis will be months and Y-axis will be counts. I created a month table listing all the month in 2021-2023 but how do I connect that to the columns (months) in my table a? Currently X-axis is not showing months (blank)

Thank you very much for your help!