Bad table manners

Idk if anyone else is dealing with this but please lmk if you are! I have a 15 month old, soon to be 16 months. He has horrible table manners. He refuses to wear a bib, he goes through so many shirts in a day. He keeps trying to climb out of his highchair, anytime we’re in public, he’s the only baby who’s standing up in their highchair and trying to get out. If we put the seatbelt on him and he can’t stand up, he’ll cry and cry until he starts gagging and we end up unbuckling it. He doesn’t take food seriously, he just sits there and plays with his food and makes a mess or tosses it everywhere. I feel like he should be past the point of doing that by now. If he puts food in his mouth, he’ll just keep it in there and not chew it for 10-15 mins. Most times he’s in his high chair for an hour+ and doesn’t even end up eating all of his food. It’s frustrating and mealtimes are NOT enjoyable at all. I try my best to cook him the best meals I can and I change it up everyday so hes trying a variety of foods. But I feel like my whole day is wasted sitting at the table waiting for him to eat and honestly I feel discouraged making him food because it just goes to waste and isn’t appreciated. As a matter of fact, my husband and I dread mealtimes because of how our son acts. Is anyone else going through this or have dealt with it?