Advice on storage for parents

My father recently informed me that he holds a sizeable amount of Bitcoin as well as several other coins. He is currently holding these all on Coinbase though unfortunately.

While we all know the importance of moving coins off exchanges and onto cold storage where we can control our own coins, I am concerned with advising someone who is not tech savy, prone to online scams, and doesn't fully understand what crypto even is, to follow the same advice. I foresee issues of him loosing his seed phrase, sharing it online unintentionally, or even using his storage device in an unsecure manner.

So I'm curious if anyone here has dealt with a similar situation or has advise on a "boomer safe" way to store ones coins