1. Yes! 12/24 word seed phrases are compatible across almost all major hardware/software/mobile wallets

2. Ledger device is fine, but I would recommend against using the Ledger Live Software and just using Sparrow wallet.

Trezor is fine, and easy to use.

I really like Jade and ColdCard. Jade is cheap and easy to use.

One device is fine for now

3. This is a grey area, Bitcoin purchased at exchanges is certainly the most KYC you can have. Whereas buying from somewhere like Bisq or RoboSats there is still an paper trail that a transaction happened, but what that transaction is for is harder to know. Cash on the street ks obviously best, but can be hard to find.

4. I dont know this is the first ive heard of Phantom

5. I don't know on this one, my guess is that it doesn't matter, but I'm not sure.

6. Probably, Phantom sounds weird 😂, and Strike is very good.

7. You use your 12/24 word seed phrase to repopulate your wallet on a different device. The 12/24 words are much more important than the device.