Where to buy a first aid kit

Hi,
where can I find all this
first aid kit, extension cords and office supplies?
thanks

You can find all those things at a home supply store, home improvement store, drug store, department store, etc. Where are you located?

You can get all these things at Tokyu-Hands, they have many stores in many locations.

Supermarkets and convenience stores will have all those things too. You don't need to go to a specific store as these are not hard items to find together.