Non-index search console issues needing resolved

Hi I have a site where we have over 1000 pages showing as non-indexed from what I can see, around half are this: I can see in search console half the errors are this https://seotesting.com/google-search-console/crawled-not-currently-indexed/

pretty much the other half of the errors is google seeing the same content twice (on two URLs on your site) https://searchengineland.com/how-to-fix-the-alternate-page-with-proper-canonical-tag-error-in-google-search-console-448852


we're trying to get this tidied up so the pages are indexed properly to help our SEO and make sure our sitemaps are set up correctly too.

Don't imagine it's a hard fix for someone with the right experience but we do need to get it resolved asap.