Flying is still one of the safest ways to travel, boring mostly, especially long-haul but it's the only way to travel to get anywhere within a short time. It would be great to cruise/ sail everywhere like I used to when I was a kid but it's no longer practical for most of us.
My advice for long-haul travel, don't eat too much before flying avoiding use of the cramped 'facilities', save space for regular fluids to avoid dehydration from the dry atmosphere. Wear loose clothing and footwear, invest in some decent headphones (preferably noise cancelling) for the inboard entertainment
If you can manage to sleep on board do so it shortens the flight, apart from that, why worry about flying?
People do it all the time, there are hundred of flights passing overhead every day and they have no issues.
Just do it.