Do ventilators remove fluid around heart, lungs?

No they do not. And in fact a ventilator cannot work with fluid in the lungs. It cannot open a lung that is in the process of drowning in fluid. You are speaking of heart failure with fluid in lungs because the heart is not a good enough pump to do its work. There is no cure for that but heart replacement. There are medications given by mouth or IV to help rid the peripheral system and the lungs of fluid. They work more or less for a longer or shorter time. Their side effects are washing out, along with fluid, electrolytes, so blood must be measured often. Fluid normally doesn't accumulate "around the heart" unless you are speaking of pericarditis in which case the heart sac can become congested with fluid. Ventilator also have a hard time ventilating lungs in covid times with the pneumonia in the lung.

No Medicines are used to get rid of fluid. If there is a lot, sometimes extra measure has to be done such as lung puncture.

No, they only help you breath. They provide oxygen and help remove CO2 from your system. To remove fluid you need other support, such as drugs.