You should think of your seed phrase or private key as the master key to your account. It is powerful. Anyone who has your master key has full access to your account. Keep it safe. Once your account has been compromised, there's no going back.
Depending on the device, Keplr wallet offers several ways to sign up for an account: Google login, Apple login, seed phrase, Ledger, or importing an existing account. Each of these methods will open a different account, so once you choose one, remember the method and keep the login info handy (and safe!) in order to access the same account.
Once a Keplr account is created, it is on chain forever. There is no option to delete, edit, or switch accounts once it's published on chain.
When sending a transaction, you'll notice a memo field. This field is publicly published on chain and can not be changed or edited after publishing.
A unique feature of Keplr Wallet is that anyone can add their chain through Keplr's "Suggest Chain" feature without permission from the Keplr team. This is to foster a more decentralized, open environment for the growth of the ecosystem.
An important point to note is that the Keplr connection with permissionlessly added chains are maintained by the chain's managing team and not by Keplr. Any troubleshooting requests should be directed to that respective chain's team.
The difference between the two is that native chains are contracted partnerships with Keplr Wallet and suggest chains can be added permissionlessly by anyone. On the Keplr wallet interface, native chains are seen from the drop down menu and suggested chains are listed under "beta."
Keplr is a gateway across networks. Behind clicking "Approve," there is an interconnected web of players outside of the Keplr team that make your transactions possible: the teams behind the blockchains, validators, node managers, relayers, community managers...
The more your learn about these other contributions, the more you'll understand how in a decentralized network, everyone's participation counts. Welcome to the Interchain community!