Tv wont switch on

This could be a problem with the power supply. Yes there is a fuse on the power supply & if you have a multi-meter & are competent with electrical safety, you could test it. However, if it has blown then almost certainly something else will have caused it. You might have a short circuit bridge rectifier or faulty chopper transistor. If the fuse is ok, then you will need to check voltages from the power supply to find out what feeds you have. There may be a start resistor open circuit for example. If most of the start up voltages are ok, then you need to look at the line output stage & check if this circuit is getting any voltage supply.