There are tons of videos on YouTube for removing the texture from a popcorn ceiling.
We wet and scraped ours off. It left a rough surface but we painted it and it looked great! It looked like we planned it. Most ceilings have a texture to them. Cover everything with sheets or paint throws to protect. Our neighbor did the same thing and he taped the 7 or 8 inch hose adapter to the scraper and caught most of his as he went! I wish we had thought of that! He painted his eggshell color the same as we painted ours. His looked great too and was much less work.
If you don't want to remove the texture, you can cover it with (depending on your style) reclaimed wood, faux tin tiles. Check out Pintrest. A word of caution about Pintrest...you can get sucked into it for hours...I have
You can scrape it. I would recommend you wet with warm water and use this tool: