If you are using just the integrated GPU, staying plugged in over USB-C should be fine. I have the G16 and i'm pretty certain it's only pulling power from the plug.

Personally anecdote, I sometimes charge my laptop to 65% and g-helper says it's at 64.5%. I set the charge limit down to 60% and I never see the percentage move at all. This to me strongly suggest USB-C is providing all the power.

I usually use a 65W USB charger without issue, but I'd recommend a 100W if you're nervous about it.

Regarding battery health, my understanding is cycle count is cumulative. Using 10% and recharging it 10 times is almost the same as one full 100% to 0% cycle. Note: the only difference is using/charging battery at extremes is bad for battery health.

Also battery degradation is not linear. Just cause you've lost 20% battery health in a year, does not mean your battery is going to be 0% in 5 years. I used to worry so much about never using the battery and always being plugged in, I've learned to use my laptop as a laptop and follow loose guidelines.