how much does it cost me to get all certificates if I want to be a pilot ?

Actually, you are a pilot once you earn your FIRST certificate! Even though you may only hold a Private Pilot Certificate or Recreational Certificate... YOU ARE A PILOT.. So maybe you want to explain exactly what you mean. (Even if we know you mean an ATP or Airline Pilot!)

$1,500 to become private. About $80K, commercial airline pilot. Even this does not guarantee a job as an airline pilot.
No one has all certs---this includes rotorcraft, etc.

No one has "all the certificates" - That would be someone with Commercial ratings for single and multi-engine land and sea, helicopter, lighter than air, rotorcraft, instrument, hot air balloon, an ATP, and type certificates for everything from a Ford Tri-Motor to an A380. It'd be fun, but no one has both the time and the money.

Let's limit this to Commercial, single and multi-engine land, and an instrument rating. You'd still need an ATP to work for an airline in the US, but with the commercial you can hopefully get someone else to pay for the rest of the flight hours needed for the ATP, and perhaps even pay you as much as McDonalds would.

The first step is the Private Pilot, which will cost $8,000 to $10,000 - there will be a range of costs on each of these. Some people require more time in training, and it also depends on the aircraft being used.

Since the commercial license requires 250 hours of flight experience, you need to build time. Since a commercial needs an instrument rating to be useful, and a multi-engine rating to be marketable, those would be next. They would help build time toward the commercial Figure another $8000 - $9000 for the instrument, $5000 to $7000 for the Multi Engine.

At this point you would have around 140 hours or so. So now you need to work on the experience requirements. Logging another 80 hours will run $10000 to $14000.

The commercial license is not really that difficult - it's much like the private pilot, but on steroids, but it will require time flying a complex aircraft, so the cost per hour is higher. Figure $7000 to $10000.

Add those up, and you have a range of around $42000 to $50,000. Flying newer or higher performance planes for the training could double that.

Far less than what it would take to study useless horsecrap like Gender Studies.

To become a pilot (and start to earn your first dollar) you will spend at least US$ 80,000 minimum - and your first wages will be dismal...
Besides the cost, it takes about 2 years pìlot training in a flight school -

And do not imagine that would qualify you to be with an airline...
For major airlines, in USA - it takes any 4-year college degree...
And in addition a few years of experience as pilot (flight hours) -

According to the programme about Easyjet a few weeks ago, getting through flight school costs around £100k

More than you have in your piggy bank, little Snowflake.