Don't fret.
After >25 years of playing "A" level rugby, I've had 3 knee surgeries. Even got the doc to shave off a couple of inches, so I can lower my saddle.
As has been said, you'll be out for a few months.
Just follow physio to the letter, and don't push it. Re-tearing the mended knee can happen easily (done it).
Good luck.
Geoff
So.... it is april fools day. My knees always hurt boating, unless it's a small creek with frequent scouting. So scout more often, and when you get that new kayak, bring it down to alf so lots of people can make you feel guilty, but they'd still boat with you
The three most important things about any surgery are: PT,PT and PT. I've had three spinal surgeries and looking down the barrels of the fourth and done medial collaterals twice. Body hurts somewhere every day. Right now you are in the dumps from the bad news. Get several opinions, go with the one you like most and maintain a positive attitude. You can and will get back in your boat (albeit with maybe a little higher saddle).