In this regard, there's a world of difference compared to twenty-some years ago when I first set out to study English.
Literal
This point [regarding-に関しては], I [subj-が] English study [obj-を] aspired-to twenty-some years-ago [with-とは] generational-gap [gen-の] feeling [subj-が] exist [polite-ます].
隔世の感 literally 'a feeling of a separated generation' is a set expression for the astonishment at how drastically things have changed. 志す (こころざす) 'to aspire to / set one's heart on' is a somewhat literary verb for dedicating oneself to a goal. ２０数年前 uses 数 'several' as an approximator — 'twenty-some years.'