Make archived posts ascending and without page breaks

I have created a blog archives page. I would like the months to remain in descending order (as with the current blog), but the posts within each archived month to be ascending, ie chronological. I would also like people to view an archived month as one continuous file, rather than keep clicking on older posts.

I know these questions have been dealt with before, but the solutions require more coding expertise than I have! Could some kind soul tell me what code I need to insert, in what files and where in the file.

I’m using the chunk theme and have set up a chunk child theme. One day I will get round to learning about php etc – honest.