I have Pokemon Fire Red, so it might be a bit different. What I did is I got the silph scope and identified the Pokemon in Pokemon tower (lavender town) then I defeated the grunts and followed Mr fuji home. You should be able to enter the buildings now.
in a house in saffron city next to the tall blue building
Silp co is a building in Saffron City. If you met Silph Scope, it is in rocket hideout, rocket game corner in celadon city.
from Sabrina in saffron city
in saffron city
You have to beat everything in the city to the left of saffron.
That building is in saffron city.
Saffron city.
Saffron city.
The largest building in Saffron City...
You can find it in Silph Co. (received from the President of the company). Silph Co. is the big building in Saffron City.
its in saffron city........ the big building in the middle of the city
In Silph Co. in Saffron city. After you get to the top of the building.