A Walk Together Can Be Enough of a Plan
You want time as a couple, but neither of you has the energy to organise an evening out. A short walk can offer a change of scene without much preparation. It also gives you a reason to put the household to-do list aside for a while.
Keep the invitation light
Ask whether your partner wants company rather than presenting a step target. Choose a distance and pace that suit both of you. If walking is not comfortable, another shared activity can serve the same purpose.
Let conversation find its own rhythm
You can talk about your day, notice the surroundings or enjoy some quiet. Every walk does not have to become a relationship discussion. Make it something you want to repeat, with room for either person to prefer a different plan sometimes.