Wait until it fruits to taste it. I’ve never heard of fruiting pears on own roots I would assume it’s rootstock. pears are easy to graft even if you have never done it before

You have a root there in the ground which means that if you graft scions to it the usual wait for a long period of time will be reduced immensely.

Here is a link to pear scion sources.

Fedco in Maine

Scion is pronounced as though it were spelled cion. You need grafting tape which you can find on eBay for $5 or so, including shipping. I use a retractable safety knife to make the cuts. I also use the bottom off a half gallon milk jug with a hole in it for a safety device. You can make multiple grafts from most scions. You can make a graft to each one of the branches on your tree. They can all be different varieties of pears. You could also leave one of the branches to see what you had. You can graft to that one later if it's not so great.

Here's an article on Whip and Tongue grafting, and a large collection of orchard videos.

You can practice on any branch from any tree about a 1/4 inch in diameter.

edit

Whip and tongue grafts are usually done late in the winter. Most sources ship in March or April. I would do the grafts shortly after you receive them on a nice day.