Please contact your attorney with specific travel questions, so that they can advise on the legal strategy for your case. Generally:

If you are in a non-immigrant status (ex: F-1, O-1, TN, E-3, J-1, etc.), you can travel internationally and re-enter the U.S. in the non-immigrant status even after your I-140 is filed and/or approved. However, there will be international travel restrictions at the I-485 stage. You will not be able to travel internationally from when the I-485 is filed to when the advance parole (AP) is issued, which could be several months.

If you are in a dual intent status (ex: H or L), you can travel internationally and re-enter the U.S. in H or L status after your I-140 is filed and/or approved. You may also travel internationally and re-enter the U.S. in valid H or L status even while the I-485 is pending.