Compare which pages appear and receive clicks under matched dates, countries, devices and page filters. Use GA4 or other on-site data to investigate what visitors do afterward.
CTR divides clicks by impressions in the selected scope. Average position aggregates search impressions, so it may differ from a single search. Changing query or page filters changes the underlying population.
Search Console clicks and GA4 sessions count different things. Clicks are not necessarily larger, and the values need not always differ. Investigate large differences through implementation, consent, dates, time zones and URL aggregation.