If a person who is not from the west is going to London or any other western country for the very first time what airport tips?

Or advice would you give?

I'm scared what if i lose my luggage after arriving over there and how should i make an exit after getting my luggage to the way from where my relatives can pick me i have been on domestic flights before but have never been on an international flight and to a majority english speaking country i know the airport basics are same in every country but usually airports in the west are very big and there are many terminals etc so it could be very confusing for someone who is not from the west and can read or write english but is not fluent in speaking please help

If you can read simple English you should be fine. All the signs are in English. And all the other people on the plane will be doing the same thing as you: picking up luggage, and going out of the terminal, and many of them will have people waiting for them just like you. Yes, there may be many terminals, but you are only arriving at one of them. It will say which one on your itinerary. Make sure your relatives know which one.

Your relatives can find out before you arrive which terminal you will land at. They will go to the point where you come out from Customs and Immigration.
If you don't see them there immediately, don't wander off looking for them: stand still and let them find YOU.

Seriously what is it you expect?

You get off your flight you go with the rest of the passengers to the passport control place and then the customs inspection place.

You will be asked some questions. YOU ANSWER THEM. If they want to look inside your stuff they will.

If they are satisified all is in order you go to the one and only one exit of the inspection area.

Your family will be waiting outside near the exit.

AS your family will be picking you up is there some reason you do not ask your family where a good place to meet would be.Near the fountain. By the clock or whatever thing is at this Airport.

Yes it is true some Airports are very large. It is organized you have no need to wander from one end to the other. International flight are all in the same area of the terminal. Or if many terminals in just a few of them. Your friends/family can find the one you will be at.

SIGNS at Airports are designed for those that do not speak the local language.

As you can ask this question in English your language skills can follow the signs.
If you want specific help for a specific Airport ASK. Every Airport in your country is not exactly the same. As the others.

YUes it matters if you are coming to Germany or the USA or Portugal or Japan or Australia or do you need a list of 200 countries?

I'm scared what if i lose my luggage. EXACTLY the same as if you loose your luggage in your Airport.
You report the loss to the Airline. They may find it. If they do not they pay you some money.
You go out and purchase new stuff.

Tens of thousands pass through London Airports everyday from the east, west north and south. There most likely will be many there that speak your language if that becomes necessary.

Suggest you start first with a map of the Airport you are landing at.

After passport control and customs, you walk out into a roped-off section, where you will see a lot of people around the outside, waiting to meet passengers off the same flight. If you don't see your family immediately, stay there, standing within the roped-off area so that they will see you. If you go outside that area, you will be in a mass of moving people, and it will be harder for them to find you.

There's clear signage in airports. If you get lost, ask a member of staff.