Two common ways:

- Order/buy stickers with Russian letters. In online shops or elsewhere. It is certainly not a problem in France... I'm not sure baout Morocco:(
Also you can just draw them on keys. With correction pen/fluid.... Or with regular paint:))))

- phonetic keyboard layout. It can be instaled on Windows PC without a problem.

When Russian 'т' is same key as  't', б is b and so on, and some exotic letters are at exotic place.

A.Jade, I dont' know.

I've just put "Russian keyboard stickers" in Yandex (it is our competitor of Google) - it immediately suggested me "russian keyboard stickers with glowing effect":-) So there are even such things as glowing letters (both Russian and Latin qwerty).

I checked Amazon (prices start from $2), eBay and aliexpress.
Aliexress is the cheapest, with options below $1, and it ships to Russia for free, but not sure about Morocco:(

There are transparent ones (they leave your Latin letters untouched).
There are non-transparent (also have querty or azerty Latin - there are azerty stickers on Amazon)
Non-transparent glowing stickers:)
There is non-transparent Latin/Greek/Russian, so may be there is even Latin/Arabic/Russian one aomewhere....? Yes! Amazon has them.

But thing about Amazon is shipping prices. For stickers they charge $4 (to Russia)