Hi there, Zack from Online DMV here, hope I can help!
If your driver's license just expired, you can usually still renew it either online, by mail, or in person. Granted, the process will be different depending on which state you're in - you hadn't mentioned, so make sure to contact your local DMV to get the specifics!
Also, if you lost your driver's license or it was stolen, you'll typically have to visit the DMV to get a replacement. They might also want to ask for some paperwork from you - normally some proof of identity (i.e. your passport or Social Security). I'd recommend checking with your local state's DMV to figure out specifically on what you need to do.
Sorry if this is too vague, but do let me know if there's anything else I can do to try and help
