I want to study here. But I have h4 visa how can study here

There are 2 choices for you...

You can go to school on H-4, but you won't be able to obtain OPT.

OR

File I-539 to change status to F-1, you will be able to work on OPT after graduation for one year BUT if you are unable to fine a job on OPT in 90 days, you have to leave US immediately, PLUS you will not be able to change status back to H-4 in US, you must file for a new H-4 at the US consulate in your home country.