Is there any way to add funds through eshop without paying at all even if it is through freeshop because I need some games for my switch I got for Christmas

Nintendo likely keeps track of the codes used, and uses trap codes to detect brute force. That would just get you banned.If it was possible, it'd be done like 2 years ago. It's literally impossible unless you made a quantum computer to easily generate valid eshop codes, else we'd be waiting a couple of years, and it'd be cheaper just to buy an eshop card.

lol . . . wait till Christmas and steal everyone in your neighborhoods mail you may luck out . . . and get a role in "the Grinch 2"@OP the only way is to shoplift eShop cards, and even then they (probably, industry standard practice) have to be scanned at the register to be activated. Not worth it IMO.