The phrase "got lay of land" means that one has become acquainted with a new situation or environment and has a good understanding of it. If you want to use a synonym for this phrase, there are several options. For example, you might say that you've "familiarized yourself" with the area or "surveyed" the space. You might also "scoped out" the scene or "mapped out" your surroundings. Alternatively, you might say that you've "gotten the hang of things" or "acclimated" to your new setting. No matter which synonym you choose, the important thing is that you feel confident and comfortable in your new surroundings.