When you feel like you can, you will. If you can do the things you want to do, you will feel better about yourself, and less dependent on others. That's what strength training can do for people. I think the best time to Do it is the time that you do it. There really is no best time.
Some people prefer to strength train after a walk because the muscles are warmed up.
Others prefer to do it first thing in the morning and get on with their day. The only exception is sometimes for cardiac patients who very early morning exercise may not be the best decision. The doctor can help the person decide about that. But there are no studies to show one time during the day is superior to another. It works whenever you do it.