You’d be surprised. I learned on a 65L and I could duck-dive that thing up to head high surf at 82kg. But I was worn out by the end of the session.
There are some great comments here, I’d add another suggestion if you can afford more gear… I picked up prone and SUP prone together. Prone for waves and SUP waves in order to get to down winding eventually. The 2 setups really complement each other. Prone really helps with pump mechanics and SUP really helps with reading the waves (you stand up and see everything) and catching more waves = time on foil. Also, connecting waves is much easier with a paddle in your hand to paddle pump. The key to connecting waves is a clean exit from your current wave. Exit with speed, hight on the mast and shallow angle, do tiny pumps with low amplitude (to maintain speed and hight) as you wait for the water to settle down a bit before turning the board back to the line up. You got this.
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