In the coming days, my new smartphone will be delivered and I ask myself the question "how do I get all my data, dates, calendar entry, etc. On my new phone?" Both devices are Android system and from the same manufacturer - Huawei.
By syncing it to the same Google Account on the old device as on the new phone.
Everything else (WhatsApp, Threema, Signal, etc.) You get over the respective backup functions over, eMail should normally be on the server anyway. With SMS unfortunately looks bleak.
In Huawei you have in the settings the function "data transfer". So you can transfer everything from your old phone again.
To redirect Google Account. You can't do more. Everything else just by hand.