Buy more bikes
I am only half-joking. If you mostly ride paved roads, try gravel/dirt road riding. Or off-road trail riding. Or if you are already trail riding, try it on a very different sort of bike.
I ride on the road and also mountain bike. Sometimes I get kind of board with one and I won’t do it at all for a while and just focus on the other.
Back when I was mountain biking several times every week, riding the same local trails over and over on my full suspension bike started to get a little boring. So I got a rigid single speed, and it was like riding a whole new trail system.