What a good package includes
Wheels and tires mounted and balanced, so they go straight on the vehicle.
Lug nuts with the right seat and thread for the new wheels. Many aftermarket wheels don't accept factory lug nuts.
Hub-centric rings if the wheel's center bore is larger than your hub.
TPMS sensors installed and ready to program, so the tire pressure warning keeps working.
Check the fitment is for your exact vehicle
Year, make, model and trim matter. Two generations of the same truck can have different bolt patterns, and different trims can have different brakes. A package matched to your exact vehicle has already covered bolt pattern, center bore and caliper clearance.
Check the tire, not just the wheel
It's easy to focus on the wheel and accept whatever tire comes with it. Check the tire type (all-season, all-terrain, performance, winter) matches how you drive, the load index matches or beats your original, and the overall height is within about 3% of your current tire.
After installation
Torque the lug nuts to the vehicle's spec with a torque wrench, in a star pattern, not with an impact gun at full power. Re-check the torque after the first 50 to 100 miles: new wheels seat in.
If the steering wheel isn't straight or the vehicle pulls, get an alignment. New tires deserve one anyway.
Keep your original wheels and tires. They're worth something as a winter set or for resale, and they're your reference if you ever need to compare fitment.
Questions
Is a package cheaper than buying wheels and tires separately?
Often, once you count mounting, balancing, lug nuts and TPMS. More importantly, it removes the risk of a combination that doesn't fit.
Can I install a wheel and tire package myself?
Yes, if you can safely lift the vehicle and have a torque wrench. Many buyers have the package shipped to a local installer instead, which also handles TPMS programming.
Do I need new TPMS sensors?
Either your current sensors move to the new wheels or new ones are installed. New sensors are the easy route and keep your originals in the old wheels.