You do not need to obtain an H-1B before applying for lawful permanent resident status. You may want to, depending on how long the adjustment of status process will take. You do not provide enough information to make that determination. Also, you should not disclose information about your employer and clients since this is a public forum.
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You are not required to have an H1B status before applying for green card but most people take that route for a reason. Processing times vary for each category. Best Wishes!
Attorney: Immigration Law
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