Unfortunately, there isn't much we can do on this end besides confirm tracking shows delivery, but these are the best steps to take:
1. Wait a day to see if it arrives tomorrow (your carrier may have just accidentally scanned it and this is super common)
2. Check with neighbors/family members to see if it got delivered to a neighbor or a family member may have brought it inside (also super common)
3. If you are in an apartment complex check with the office staff, sometimes packages get left there instead of the tenant boxes
4. Call your local USPS and ask for a "GPS coordinates" on where it was delivered and that way you can confirm it was delivered to the correct location and hopefully not stolen etc. or if was delivered to the incorrect location and they can recover it for you.
5. Speak directly to your mail carrier as they will be able to confirm where it was left.
6. If your package was shipped priority method then your package will be insured and you can claim that with USPS.