Basic rule of thumb- Motors last longer than airframes

Either wait and get a plane and motor that will allow you to get started in pattern, or get an airframe that will allow you to fly well with the motor that you have. Any 50 size plane with "pattern proportions" should be fine... but it isn't going to fly like a full 2 meter pattern plane. You can't have both!

Anything (literally) can be set up to fly sportsman pattern- You need to begin learning how to set up, and trim an airplane for precision flight, then you need to begin practicing precision flight. Most novices either give up before they can fly straight and level at 150 meters parallell to the runway, or just skip that step and never get good at it. re-read what Arch Stafford told you.