I'm virgin in these games, so please, I need guidance :P

I have seen this on Amazon:
https://www.amazon.co.uk/PXN-2113-Joystick-Simulation-Controller-Vibration-black/dp/B01J7O0G4Y/ref=sr_1_23?ie=UTF8&qid=1511647315&sr=8-23&keywords=flight+stick

Is it good?

Thanks a lot!

It's probably a cheap clone of the logitech 3D pro.
Joysticks are something that get stressed a lot so going too cheap or off-brand is not advisable and many of these no-name brands skimp on components, often adding stuff like the vibration function that is almost always not supported and really doesn't add anything but one more thing that can break, especially at that price.

These are better options:
https://www.amazon.co.uk/Thrustmaster-T-16000M-FCS-Joystick-PC/dp/B01H6KXGEI/ref=sr_1_1?ie=UTF8&qid=1511728004&sr=8-1&keywords=t-16000m

https://www.amazon.co.uk/Logitech-Extreme-Pro-Precision-Joystick/dp/B00CJ5FPTA/ref=sr_1_1?s=videogames&ie=UTF8&qid=1511728171&sr=1-1&keywords=logitech+3d+pro

The Logitech is an old model, the thrustmaster is a bit more recent (and uses magnetic sensors rather than potentiometer, which is convenient at this price range since cheap potentiometers can be less reliable) and can be upgraded to HOTAS by buying the TCWS throttle, but they are both programmable (which is very useful with older games) though the Logitech software for the joystick hasn't been updated in a long while (technically it has but newer version don't support joysticks so you'll have to download an older version) while T.A.R.G.E.T. is still fully supported by thrustmaster.

Regarding brands, the good ones remaining are Logitech and Thrustmaster when it comes to cheap stuff, the other two big name brands, VKB (Russia) and CH Products (US) are mostly specialized in more expensive stuff.

Thanks a lot!

I see that Thrustmaster is quite good, probably I am buying it!

I see it can be upgraded with the throttle. Is it a must for most games? Or just for pure, deeper simulators?

A throttle is great for any kind of flight games, both arcade and simulators.
The principle is having control of the throttle while having at the same time a bunch of buttons and hat switches handy for additional functions to avoid using the keyboard.

HOWEVER:
1- It's not convenient unless you are someone like me who plays these games regularly as it's quite a bit of money (for example in my case: when I only have a half hour of game time 75% of the time my choice of gaming is a round of X-wing vs Tie Fighter or some other of the spacesims I keep perma-installed on my PC);

2- Many titles do not support it out of the box and require a bit of fiddling with the joystick software to create game profiles that make the game believe the throttle and the stick are one virtual peripheral;

3- some other do not support a throttle axis at all (DOS games mostly), some have speed preset keys that can be easily programmed on the throttle axis using the joystick software (I did so with the older X-wing games using CH Control Manager for example and I know for sure it can be done with T.A.R.G.E.T.) others like the older Wing Commander games do not have them and making it work in some fashion requires advanced scripting and even then it never quite works like a throttle (I did it with Privateer just for the hell of it using CH Control Manager and while it was functional it didn't exactly act like a real throttle).

Bottom line: if you just want to occasionally play Wing Commander games and other spacesims the joystick is enough, the throttle while a VERY nice addition is still something more for enthusiasts.

Thanks a lot once again!

I think I will buy the Thrustmaster one and later, if I become more experienced in the genre and feel in the need of giving a step forward, I will buy the throttle.

Thank you very much!