I am currently working in USA, under valid H1 Visa. I am planning to change my wife visa status to H4 she is currently on F1 OPT

You should go to the uscis.gov website and check out form I 539.

I hv an option of filing I485 from NJ or California. which one will be faster as it goes to different service centre ?

Honestly, in the end it would not really matter. The times they post online are not accurate, so file it where you actually reside/work. Good luck.

Can I apply for work and holiday visa Australia if I green card holder

You should contact an Australian Consulate and ask them.

KI visa, status change, alleged domestic violence.

You can tell your wife if she was invited on a K1 visa, she can get her green card only through you. Or, she can leave the country. A VAWA petition...

I-94 and Asylum application

You may send a letter to the local asylum office with this information prior to your interview.

I-325A employment section

You should discuss this issue with an attorney in private, not on an online forum.

You need to wait for the official notice by mail.

Does having an H-1B Cap Exempt visa give me any advantage when later applying for an H-1B Cap Subject visa?

No advantage. Only the experience, I guess.

I have a 10 year visitor visa, how can I start making steps to finding a job in the US? I am currently doing Level 2 of my CFA

You would have to submit your applications to various employers.

When does DHS announces TPS termination notice?

You can subscribe to USCIS updates and get the notice to your email.