in general, if you show intent to immigrate (and someone petitioning for you to do so is a pretty convincing sign that you do), they will be much more strict on letting you in as a tourist. many people want to bypass immigration procedures by just entering on a tourist visa and then adjusting status later or waiting for a decision in the US. they won't allow that. so, more likely than not, they will not issue tourist visas to people awaiting a green card, unless they have very strong ties to their home country - a job, a house, a car, other family members etc. even then, it's up to the consular officer to decide if you are likely to return after your 90 day tourist visit limit expires or if you are at high risk of overstaying and can deny you regardless.

You Can Come Over Tourist And Other Visa If You Don’t Show That You Have Filled An Immigrant Visa

Hey, they can come on tourist visa, but they can’t adjust their status until the visa is current and they must maintain lawful resdence inorder to adjust