Hello, where can I buy stationary and small personal electronics such as cell phone cables? Is there a place near the seed Square? Is there an auchan with more than groceries?

Thank you

Can't be much help to you. Last time I was in Moscow there were lines outside the GUM store on Red Square in the middle of February full of sad faces waiting to buy bread. Pre cell phone days.

Last time I was in Moscow .( a year ago)'GUM was filled with designers stores and
people were enjoying the food at a nesrby McDonalds and numerous other
eateries...(from Italian to Russian to French).

Best to ask at the hotel.

I presume you mean Red Square?

They have a lot of Samsung stores in Moscow, they might have the electronic things you need. There is one in GUM mall.

yes, Auchan sells more than food, have you been in one? They aren't in the center.

https://www.auchan.ru/

See all those little pictures on the left side? that's stuff they sell.