According to Microsoft's Support website:
To restore a database, you must already have a backup copy of your database.
This is true of essentially all data-loss recovery situations. You should consider your data utterly lost unless you have a backup from which you can restore.
Having said that, there may be options for you to recover, but every single action you take on the computer affected may make each recovery option less likely to succeed. Depending on how critical this data is, you may want to simply remove power from the computer now and image the disk drive to preserve possible forensic recovery. Other lower-impact but correspondingly-less-likely-to-succeed options may include duplicating the MDB file onto external storage.
This is only "Step 1". The next steps would involve analyzing the data you've preserved and trying to extract the data you need. With a disk image safely made, you may be able to boot the computer back up and check Volume Shadow Copy to see if there are any older revisions of the MDB file.
You need to weigh the time investment you're willing to make against the possibility that your data is simply gone. No recovery option is a guarantee and you could spend hours, days, or weeks on recovering the data that was deleted.
And having said all of that, not to needle, but having a backup routine could have avoided all of this.