When Google released v5 of Analytics in 2011, they made a small change that allowed the Page and Previous Page Path dimensions to be used together, but that made the Next Page Path the same as the Page dimension and caused the confusion that continues today. You can read more regarding this in below article

URL: https://help.analyticsedge.com/article/misunderstood-metrics-next-page-path/

URLs also appear to be the same because of the varying IDs Or page parameters in the URLs. for this, you can consolidate them with a search and replace filter but that's outside the scope of the configuration and support of the app.

You can find more details regarding this on the below URL.

URL: https://www.getelevar.com/analytics/funnel-analysis-hack-view-next-page-path-in-google-analytics/