I am currently living in Russia and I've never checked whether there' are food kitchens for the needy nearby.

When I and my farther and I lived in Montreux, Switzerland, we used to ride a bike to the food kitchen which was situated in the neighbouring town.

For two euros, you could buy a pack of different foodvarious food items and have lunch right in the kitchen, while the same food in nearby shops was by threehold times more expensive.

I am currently living in Russia and I've never checked whether there' are food kitchens for needy nearby.

You can't use that contraction with there. It sounds weird.

When I and my farther and I lived in Montreux, Switzerland we used to ride aour bikes to the food kitchen which was situated in the neighbouring town.

I am assuming you two didn't ride one bike.

We pedalled there two times a week: Oon Wednesdays and Fridays.

I don't think the original is wrong, this seems more natural to me.

For two euros you could buy a pack of different food and have lunch right in the kitchen, while the same food in nearby shops was by threehold times more expensive.¶
¶
or¶
was more expensive by threefold.

Three times = 3x, commonly used.
Threefold isn't commonly used in American English.

We only bought the red fish at the local shops.¶
¶
In the local shops we only bought the red fish.

I feel as though your sentence conveys a slightly different meaning, as if there was only one red fish in all the shops.
I'd just figure out what kind of fish it was. Red Snapper? Tuna? Or explain more about the different types of fish and why that decision was made.

I am currently living in Russia, and I've never checked whether there're food kitchens for the needy nearby.

When I and my farther and I lived in Montreux, Switzerland, we used to ride a bike to thea food kitchen whichthat was situated in the neighbouring town.

"I and my father" sounds unnatural here. You can also use "me and my father," which, while grammatically incorrect, sounds more natural.
I recommend adding several commas anywhere you might stop and take a breath. Otherwise, your sentences tend to get long and hard to read. When you listen to English-speakers speak, notice where the pauses naturally fall in conversation. This will give you a good idea of where to put your commas.
If you're talking about a particular food kitchen, or "the food kitchen" as it were, you could say "we used to ride a bike to the food kitchen. It was situated in the neighbouring town." Notice that you use "it" or "its" when talking about something you referred to with "the." If you're going to use "which" or "that" (the latter sounds more natural, but both work), change it to "a food kitchen."

We pedalled there two times a week: Oon Wednesdays and Fridays.

The only problems I notice here are spelling errors. Besides that, it looks great!

For two euros you could buy a pack of different food and have lunch right in the kitchen, while the same food in nearby shops was by threehold times more expensive.

I've never heard the term "threeholds" before, unless that's a short way of saying "three thresholds." "Three times more expensive" sounds more natural here, instead.