The first route, at Aoto you will stay onboard the train and then alight oshiage. Need to exit from the Keisei station and then enter the metro station.
Then second route u stay onboard until nihonbashi then u exit the Toei station and enter the Metro Station.
get the IC Card at the airport (Suica Card) then it is easier to enter and exit instead of buying physical ticket.
For most train lines in Japan, as long as you switch between different operators, you will need to exit and enter again. in some stations, there are multiple operators. In Singapore, we got smrt and sbs and we don't need to exit and enter to transfer operator but in Japan tokyo they got metro, JR, Toei, Keisei, Tokyu, Tobu, Seibu, Keio, Odakyu, Keikyu etc
Alternatively as Gixxerfied mentioned, at 4:22pm there is a JR direct train Narita express which goes from T2 to Shibuya without any switching trains. Cheapest will be 3190 Yen and take around 76mins.
aiyo. why so many transfers? just take to Ueno, then take Yamanote line to Shibuya la. estimate 2-2.5hrs