Don't delect: H1 and first job

Ask for a friend. Don't know how to answer him.

He has a Ph.D. and on OPT, but couldn't find an appropriate job. He's doing several part times. Now, one of the part time jobs has an immediate opening. He can get it if she apply, but the level and salary is very low.

While the job can help him get H1, he's afraid that if there is another better position to fit his degree, he can't get promoted from a very low level to a high level (because of the cap policy. Anybody know what this is?).

Thanks.