One that was designed for air rifles. Best will be determined by your intended use and how much you spend.
Only if the scope is designed for an air rifle. Because of the recoil being different on an air rifle than a firearms rifle. Air rifle scopes are made differently than firearms scopes. A firearms scope can break it's glass mounts if it is used on an air rifle.
Some scopes can cost more than the Air Rifle. Leapers makes some excellent scopes for around $250. Whatever scope you purchase make sure it is designed for air rifles. Air rifles, because of their forward / reverse kick, can break a regular hunting scope not designed for this type of rifle.
Almost any air rifle scope will fit a Daisy. Check Walmart or a sporting goods store for a Daisy scope. But any air rifle scope should fit the dovetail mount that is on the rifle.
A 4 x 12 x 40 works great. Just make sure you can adjust the parallax down to 10 meters (or less) and that the scope is air rifle rated. The recoil of some air rifles will destroy non rated scopes.
TASCO
The best you can afford.
Yes it has an 11mm Dovetail scope mount
If it has a scope rail or grooves for a scope mount then yes it will support a scope but you may need a scope stop to keep it from moving.
Only if the scope is designed for air rifles. Regular firearm scopes are made different than air rifle scopes and many will break if used on an air rifle because the recoil is different than a firearm.
Best left to a good gunsmith.
A scope for an air rifle can be bought at many different places. You can buy one in a gun shop, in a sporting goods store, or even in a pawn shop. You might be find one for sale in your newspaper.
A rail interface system or a mount on the top