I'm trying to start suzuki 1999 katana 750 from the winter storage?Which is the correct & best steps for doing so? Thanks

So on my 1997 Suzuki 750 katana lost power on the dash bike still runs but not sure if it’s a electrical problem

Depends on the mileage. If it is high mileage, use synthetic.

carbs are dirty try this spray starter fulid only 2 to 3 sprays do not exsead
more if that works run it if not running right pull carbs off and bowls clean them do not touch any more then that if you dont know what your doing

replace the fuel filter

if you follow your positive battery cable from the battery it will lead you to the starter relay. in the starter relay there is a 30 amp main fuse. check that main fuse and replace. if nothing still comes on, there's a good chance you fried yor computer.

Right side of bike, there's a small round cover you remove.

Put the battery on charge - while it is charging remove and clean the sparkplugs - once the plugs are clean and refitted also make sure all the HT leads are secure - check the fuses, have a once-over of all the connectors and cabling and make sure everything is dry and secure.
Likely the battery was never fully charged to begin with - but still clean the plugs since they will be fouled from the non-starting.

I would be checking main fuse not much more it can be