Beside that, is that possible our sun became pulsar? And if not (and i know likely) but how much more mass does it need to become one ?
There are at least two types of supernovae (SNe): thermonuclear supernovae (TSNe) and core-collapse supernovae (CCSNe).
TSNe come from the explosions of white dwarves (WDs) in binary systems. A star with mass at zero age about < 8 solar mass, it normally evolves and ends up being a WD. Our sun is in this category. So, we expect our sun to evolve to be a WD and give no SN explosion without further perturbation.
Massive stars (> 8 solar mass), by themselves, evolve to CCSNe. Some of these events leave compact objects either neutron stars or black holes.
A pulsar is a rapidly-rotating and magnetized neutron star (or white dwarf but very rare) with misalignment between the rotational axis and the magnetic dipole, and it beams the EM to the line of sight. Speaking of that, if we consider the pulsar as a special case of a neutron star, the progenitor star should have its zero age main sequence mass > 8 solar mass, for ending up in CCSN and hopefully leaving a neutron star as the compact object. Therefore, it is less likely for the sun to be a pulsar at the end of the tunnel. How much more mass? This is even harder to tell because that means the sun has to evolve in a binary system, where the evolutionary path is even more diverse and harder to predict.
What's more, there is a path to supernova involving less added mass, and that is if the Sun is first allowed to become a white dwarf, then it would only require one more solar mass to be added to create a type Ia supernova. But that would not make a pulsar, and it isn't any more likely to happen than adding 7 solar masses.