does the

Please state the country about which you ask. In the US, the answer is no, and I suspect that is true for all other countries, but can't really say.

current not reaches the sub station ,voltage will passes the circuit like television,lights etc and returns through neutral wire which it is return wire and it is grounded at the transformer near the house.

actually current will not flows, you are thinking that it is a current,but it is voltage.

how to know the current means for example

when you are watching the screen of the television, at the time program is running then the work is done and hence we measured that work as a current

consider the two magnets of opposite poles(S-N) which faces together at that time repulsion will occurs between them at that time we cant see the current,but we can measure.

>> does the current reaches the substation through the neutral
>> wire from the various houses

Current can be though of as a "flow" similar to water, and if that analogy is used, and if the distribution system you are contemplating is a grounded-wye system, and the various houses are connected single-phase, line-to-ground, the answer is yes. But there are a lot of qualifications in that yes.

In a grounded-wye, three-phase power system, even single-phase loads tend to cancel out the neutral current from loads on other phases, so in a well balanced system the neutral current on the distribution system close to the substation will be a fraction of the current on the phase conductors.

Note that there are delta distribution systems that do not have neutral conductors.

How did I get an off-topic for saying "no" here?

In an ac system like the US, the residential service comes from a center-tapped transformer secondary. That center tap is the neutral.

If the two phase loads are perfectly balanced, that neutral does absolutely nothing and could, in fact be removed.

If the loads are moderately unbalanced (as is usally the case), the neutral has a smaller current than the phases.

If all the load is carried by one phase, the neutral has the same current.

But, current doesn't really flow from a substation to a house and back. Actual charges move back and forth only about 2 X 10^-6 meter. It is energy that "flows" from the substation and it doesn't come back.

Off-topic. Sheesh!