Earlier quoted context omitted.
Find a competent trainer - gyms that teach Olympic Weightlifting are going to have higher caliber trainers than the typical commercial gym full of 'personal trainers.' There's a massive technical aspect to learn that puts a more scientific spin to appeal to people like us.* * You're on HN, right?
Training to be better at something that you will never do for real is somehow depressing, especially if you only do it in a gym. Run or ride a bike, at least you have a chance to do something useful instead of moving a weight for the sake of moving a weight
If you pick up heavy stuff off the floor, that's a deadlift.
Put something on a shelf, it's a press.
These items are less a problem in your 20s, 30s and below, than above.
More muscle mass means more hormone production, which otherwise declines with age.
And weightlifting leads to higher bone density and stronger tendons.
Now are you sure it's not useful, moving a weight for the sake of it?