I meant a website that generates just the design and lets you copy-paste in a text field the private and public keys, automatically generating QR codes for them. All offline.
bitaddress.org will let you do this. Just click on the "Wallet Details" tab and paste your private key in. It will generate all associated WIF keys, public addresses, and QR codes.
I see. I know both of them but not knowing like anything about coding still puts me in doubt.
Don't rely on their random number generator then, and create your own entropy manually.
You could use the Ian Coleman site at
https://iancoleman.io/bip39/ (downloaded and ran offline on a live OS on an airgapped computer), and check the box "Show entropy details". You can then flip a coin 256 times and enter 0 for heads and 1 for tails, or roll a 6 sided die 100 times and enter the sequence of numbers, or even draw 54 cards from a deck of cards. Plug that in and it will use your entropy to generate a seed phrase, private keys, public keys, and addresses.
If you want to rely on websites even less, then you could flip a coin 256 times, arrange your results in groups of 4 (so 64 groups of 4), use a handy table like this one (
https://i.imgur.com/Qmhe8Xo.png) to convert from binary to hex, and then use your resulting number in hex as your private key in bitaddress as above to generate your QR codes.
