Absolutely! You don't need to pay for a subscription to get a good workout. There are plenty of free indoor walking videos on YouTube that are ideal for beginners.
At 65, I'd suggest aiming for a 20-30 minute walk most days of the week. After your walk, add a few simple strength exercises like chair squats, wall push-ups, and standing calf raises (2 sets of 8-12 reps). Those will help maintain muscle, improve balance, and make everyday activities easier.
My biggest tip is not to worry about finding the "perfect" program- consistency beats perfection every time. And remember, we're exercising to feel better, not auditioning for Strictly Come Dancing!
Best of luck- you've got this!