Well, more than likely you will need to replace the sand since stirring it up when moving the tank will unearth rotting particle called detritus which cause problems down the road. Click the article tab at the top of the page and read about fishless cycling and the nitrogen cycle. If the stuff on the inside of the tank is purple, that is coraline algae which is safe, as long as its not obstructing your view from the front and sides, you can leave it alone, otherwise try using a metal edged scraper to get it off, it will take a few of them and some work. Clean any and all equipment off that came with it and scrub and soak it in a water/vinegar solution of 16:1 or something similar, never use soap or detergents. If there was any rock included, either stick it in a rubbermaid container and pour old or new sw
over it, or you can scrub it with a new brush if it is covered in hair algae, aiptasia, or anything else that looks questionable. Use gloves when handling the rock, make sure they are thick too, since there may be things in the rock that can cause you pain if you accidentally touch them such as bristle worms.
You will need test kits containing ammonia, nitrate, and nitrite at first, then pH and a few others later. Grab a thermometer if you don't have one.
Hope this helps. Welcome to AA!