Drove my Honda Pilot 10 hours to escape COVID land. Then left it parked for 3 weeks. Now, I can move the transmission from Park to Reverse or Drive, but the car moves forward as if the parking brake is on (the indicator light indicates that it isn't on) and makes a lot of groaning noise. I cannot move the transmission to D3 or anything beyond Drive. I don't see transmission fluid on the driveway, but it has rained a lot, so I am not sure if it leaked. Any ideas beyond checking the fluid level? Thanks.
You should check your transmission fluid first, it's free and would answer an important question. Groaning sounds aren't typical of a transmission problem, usually that would be a brake caliper seized up or maybe the parking brake is stuck on. The light only comes on if the parking brake handle is pulled (or the pedal is pushed depending on your car). If you release it the shoes could still be gripping even though the light is off. Try applying and releasing the parking brake a bunch of times and see if that solves your issue.
Likewise a brake caliper could have seized in place and still be gripping a rotor, again the advice is to apply the brake a few times and see if you can't free it up.
Note that both of those are temporary solutions, and only really serve to tell you where the problem lies. A seized caliper or parking brake may release now, but the problem is likely to come back. A caliper that isn't releasing can overheat your brakes and cause failure, so not something you want to ignore.