towing boats 101
I have towed boats for over 40 years, and I am a licensed captain.
Electric brakes do not last very long on a boat traailer because of being dunked in water, and especially salt water.
Boat trailers have hydraulic brakes with a "surge" activator. Imaging a brake master cylinder bolted to the trailer and the activating rod connectred to the vehicle. When the vehicle stops, the vehicle presses on the brake rod from the momentum of the trailer, and activates the brakes. Simple and effective. Providing they work.
Most states require brakes on a trailer weighing over 3000#, loaded. Check with the state police and find out the limit in your state.
Next, buy a "towing mirror". You will need it to see vehicles in back of your rig. Again, state laws.
Before towing that new boat, check or have checked the wheel bearings in the trailer for water and to be sure they are greased. And the air in the tires.
Otherwise, enjoy your new boat.