Already tried setting a toilet on this flange, thinking the flange is too low from the floor and that's why it leakes from the base?

Where's the Was Ring?  The Wax Ring is the only thing that will stop the toilet from leaking at the toilet base.

you can double up the wax ring if the base is too low and should solve the problem.

you need a tall wax ring.

there is a special pan collar which can raise it i should know i am a plumber 

Nowadays, we can see different types of control water leak spray available in the markets. With the use of good material, we will not see this kind of problem in our life again. Hope you people understand my point of view.

Well, why don't you show this picture to the guys in the plumbing department at the plumbing shop you are going to go to? Also use a straight edge across the opening laying it flat on the tiles so they also know how far down is the flange...from the floor surface.   I see the tile work is not done so you got to do that first, meaning grout too.  (Right now it looks like a dry fit.)  If I am not mistaken they have a extra thick wax seal or a riser as well to raise the flange height.  Toilets are normally sitting ON TOP of the tiles so the plumbers have the adapters for the wax seal.  Give them that info and they can work with you.  If the clown says to cut out the tile in the shape of the toilet...MOVE to a more knowledgeable clown.

 Note with the wax seal.  It has a wax paper on it when you buy it as it is sticky wax.  You want to take the wax paper OFF and then set it on the floor so the sticky side sticks to the floor. Then take off the wax paper on the other side of the seal so it is sticky wax.   Using 2 would double the height of the wax making sure sticky sticks to sticky. There should be no paper on the wax rings.  It is stuck like bubble gum in hair.  A wax ring can last 100 years.  Now put in the brass hold down bolts so they stand upright and lift the toilet over and set down and the bolts magically fit through their holes in the toilet.  Now sit on the toilet seat cover to squish the wax against the toilet and against the floor. Now the large flat washers go on and screw down the nuts onto the brass hold down bolts which are hooked into the flange.  Do not use the wrench to scrunch down the toilet for you will certainly break the ceramic toilet.  You body weight is all that is necessary to scrunch it down and the bolts just make sure it does not move side to side. Done dat.

. Now hook up the tank plumbing.  There is no testing.  Once it is filled with water it is held down by the weight of the water until you sit your Fat A on it.  Down is the only direction it can go.

. That is why you finish the tile work first.  You are not picking it up again FOR ANY MONEY.

. This is an "idiot proof" job. Cause some plumbers been smoking that funny schit.

Where is the wax ring for it?

over at any decent hardware, you can get both free advice and an extra thick wax seal.  MEASURE the flange height above floor first.  Be prepared to be told that prior owner did the flooring wrong and it needs to be removed in the vicinity of the toilet.  -- grampa

Use an extra large wax seal - HOWEVER warm any seal up a bit - low room temps really make it hard for them to smash properly and seal. Had this problem once and ended up putting the seal in a car outside where the sun was warming the car to about 80+ F for a couple hours then ran it in and sealed it up.

Double the wax seal.