Hello. Planted lemon seed from store bought lemon a year ago. It s now in a pot on the balcony.

I would like to ask if i need to cut and prune it. Is this a sucker? Should i cut that? Do i cut the leaves on top or at the bottom. I am concerned because the balcony is small and i can't have it grow too large/tall/ bushy, and am still hoping it will fruit someday.

Thanks!