You can stretch your brain. That's exactly what learning is!
Whenever we start something new, we start small, and as we get better at it, our brain becomes better at doing it without masses of hard work. This works with practical skills like learning to juggle or learning a new instrument, but it also works with stuff like maths or spelling or learning a new language.
As we practice, our brain expands, and this is particularly true for your memory. Think your memory is rubbish and you're just stuck with it? Think again. You can learn to learn.
So practice memorising things and keep practicing. Write lists, write things down on post-it notes. The more you practice, the better you'll get. Draw things, colour things in, and speak them out loud. If it helps, grab your pet and tell them the stuff you're learning or record yourself talking through something and listen for it out on a walk.