There are quite a few ways to skin this cat. If this isn’t a table that’s worth 10s of thousands of dollars and is just being used as a standard kitchen table with kids, I’d take the steps below.
1. Sand down your top. Start with rougher paper and then work your way into a fine grit for a smooth surface.
2. Thoroughly clean the area. Wipe everything down with a slightly damp cloth multiple times. Let it dry.
3. Apply a wood conditioner. Follow the steps listed on the bottle.
4. Apply a coat of stain and let it sit for 2 full days despite what the can of stain may say for a shorter drying time. If the grain raises or things seem rough, do a light sanding. Add another coat of stain and let it dry.
5. Apply urethane (I prefer Arm-R-Seal for something with this much use). Follow the directions. I would use a minimum of 3 separate coats with a light sanding in between considering it’s a table top.
***I’m not a furniture expert, this is just what I’d do***