I’m not sure you need a chair, it may only enclose the space rather and make moving around the table a bit cramped. No need to make any decisions. Live with it for a while to see if you really need a chair. Maybe an ottoman would work just fine

No leather. Already too much light reflective and brown material in this room.

Nice sofa. Not in love with the white pillows. They break things up and pop too much.

I'm choosing an oversize ottoman instead of a table to help make a couch/sectional more loungey. Often a chaise end helps with that. I don't see one fitting to the right here.

These don't fit your space but are examples for lounging and using trays on ottomans instead of a table.

Do you mean where your dog is lying? Gets almost 5 stars, very inexpensive and isn't too big and clunky.

https://www.wayfair.com/Red-Barrel-Studio%C2%AE--30.3-Wide-Tufted-Upholstered-Armchair-X111002196-L54-K~W000991085.html?piid=551052543

Coffee table is, as noted above, very large and heavy looking.

Nice couch. It is hard to see the rest of the room to see if a chair will actually work there. But kazzh 's suggestion is a good one.