Sorry to make this complex, but you can connect a grill to either the high pressure or low pressure side of the 5W LP system, Basically that means before or after the RVs gas pressure regulator. Do you already have a Tee installed? If so, which side of the regulator? If not, you need to add the Tee and have a location choice to make.
If the Tee is downstream from the regulator, you need a low pressure grill, meaning one that does NOT use the small disposable bottles. The ones that use the small bottles have their own regulator built in and require high pressure. Unfortunately, most table top grills are of that type. It's possible to convert some of those grills to low pressure use if you are handy, and there are YouTube videos describing the procedure.
My personal opinion is that connecting a table top grill to the RV system is more a nuisance than a help. The table has to be close enough to the RV to suit the length of the connecting hose and the hose too often ends up in the path of people getting to the table. If you don't want to carry a couple of the small bottles, consider buying a 5 lb or 10 lb LP tank and a short hose, maybe 5 ft. You can place the grill anywhere and sit the small/light LP bottle under the table or at any convenient spot. The little 5 lb bottle takes little room in the RV or tow vehicle and lasts a long time.
https://www.homedepot.com/p/Worthington-Pro-Grade-4-25-lb-Empty-Propane-Tank-281149/202034835
