I use two locks and a motion sensor alarm on the bike that I make stops with. It's not an e-bike, but I wouldn't do anything different, even if it was.

A few things I keep in mind:

Thieves are the scum of the earth, and even if your bike is secure, they may target quick-release wheels, quick-release saddle, any lights or accessories you have mounted, tools, and even accessory mounts. Do your best to either have non-removable versions of these, or secure them in some other way (even zip ties). You want to make it inconvenient for someone to try to steal stuff off your bike.

Although I haven't done this, I know that it can also be a deterrent: get detachable pedal and remove them when you lock up your bike. Any thief that defeats your locks would have to push your bike around, which wouldn't be ideal for them. Removing the saddle works the same way, but just keep in mind that anything you can easily remove can be removed by someone else, so make sure you do remove them when you walk away! I replaced the quick release clamp on one bike's seat post with a bolt-on clamp, just to avoid having to worry about it.

To the best of my ability, I try to check ahead of time for bike racks and secure locations to part my bike before I head out to a destination. OpenStreetMap often lists bike parking, but I'll also use Google Street View to "see" what's there. Just keep in mind that these things can sometimes be inaccurate/outdated, but this isn't as much of a concern if it's a place you visit regularly.

If there is no bike parking, I've been known to walk my bike or e-scooter into a store. If someone says something, I'll point out that they have no safe place for me to park my bike. I've only been asked to leave the store once, and was told I could lock my bike up to the grocery cart return area, which was fine.

If the places you frequent don't have bike parking, let them know.