Can you ride in the rain? Absolutely.
What happens if you get a flat tire? You can learn how to change it. The front isn't too bad, but the back tire, because of the hub motor, can be a real pain.
I had a Pedego Trail Rider, which is very similar to your bike and I did get a couple of flats (both in the rear) over the span of 2500km. I have to admit that both times I had my wife come and pick me up. AAA is also a good option, but if AAA in the US is anything like Canada, the wait for an AAA truck could be a long one.
One very useful tool for changing your own tires is a pair of handlebar jacks.
https://www.handlebarjack.com/
With the bike upside down it is MUCH easier to take off and reinstall the rear wheel.
Slime would be a good option, as would tannus armor. Some people like the way the bike rides with tannus armor installed, while others don't.
Personally, I really like a tubeless setup, but I don't think you can go tubeless with the Trail Tracker. I have over 10,000km on my two other bikes (that I run tubeless) and haven't had a flat tire.
Another option is to replace the tires with something more puncture resistance. I got my two flats within the first 1000km then switched to a better tire and didn't have any problems in the next 1500km. Personally, I thought the stock tires on my Ridge Rider were crap.