Starts but wont shift into drive no headlights no heater blower no turn signals

Since you only mentioned drive, I'm going to presume you meant you can't shift into any gear, Is this correct? Normally, I would say this isn't an electrical issue, it's mechanical, either something in the shift column or the shift linkage is broken or come loose so I browsed the fuses in my owner's manual and you can check these fuses: fuse #8 (10A) - Shift Lock, Speed Control, fuse #14 (7.5A) - Transmission Control Switch, fuse #10 (20A) - Brake Pedal Position, Brake Pressure Switch. If you can't shift out of Park, turn key just enough to unlock steering wheel (not turn on dash lights) and see if shift lever moves. If so, then shift into Neutral and start car.

under the hood locate the shift cable and take it off the shift link and turn the link counter clock wise until its locked in position then start the car you can adjust the linkage after this step

The turn signal fuse I could see if there was a short in the wiring in the column, but the heater fuse surprises me.
It could be in the column, or in the harness going to the transmission.

The Buick Century is equipped with a multi-switch. This switch is an all in one switch that controls your cruise control, windshield wipers and turn signals in one switch. This switch also controls dimming and brightening of your headlights. The dimmer switch is simple to replace, and all you need is a phillips head screwdriver to complete the task.

1. Removing the Steering Column Shroud
   • Removing the dimmer switch starts at the steering column. To plan this task out, access the steering column by removing the screws holding the steering column shroud in place. This will expose the turn signal lever. Remove the lever by twisting it forward, and pulling it out of the switch.
     
   Removing the Dimmer Switch
   • The switch is held on by two screws and a wiring harness. The wiring harness can be removed by prying up on the locking tabs and pulling the connector out of the socket. The two screws can be removed with a phillips head screwdriver. The switch will slide out. To install a dimmer switch, be sure to repeat these steps in reverse order.
     

twist the turn signal knob?

SHIFT INTERLOCK IF YOU HAVE COLUMN SHIFT IT WILL BE LOCATED BEHIND STEERING COLUMN COVER.YOU NEED TO REMOVE LOWER KNEE BOLSTER FIRST THEN REMOVE STEERING COLUMN COVER.THE SHIFT LOCK SOLENOID WILL HAVE TWO PIN CONNECTOR.THAT WILL HELP YOU LOCATE IT.

It sounds like the shift tube bushings are worn out. There are usually 2 u shaped clamps that have nylon bushings that hold the shift tube to the steering clumn. If loose, that throws off the shift position, could be btween 2 gears at once, and throws off the park - neutral safety switch. Fix that first.


Item Part Number Description 1 14A664 Air Bag Sliding Contact 2 3530 Upper Steering Column Shroud 3 3518 Steering Column Bearing Sleeve 4 3517 Steering Column Bearing 5 3511 Steering Column Lock Cylinder Housing 6 13K359 Multi-Function Switch 7 N808114 Pin 8 N805857 Steering Column Release Lever Pin 9 3D544 Steering Column Release Lever 10 3F609 Tilt Wheel Handle and Shank 11 7361 Column Shift Selector Lever Plunger 12 7210 Gearshift Lever 13 3D657 Steering Column Shaft 14 7B071 Transmission Control Selector Lever Plunger Spring 15 7G357 Gearshift Lever Pin 16 7212 Transmission Column Shift Selector Tube 17 N806582 Tilt Column Pivot Screw 18 7C464 Transmission Control Selector Lever Spring Clip 19 7E400 Gearshift Tube Bushing Clamp 20 - Spacer (Fixed Column) 21 3E729 Steering Shaft (Fixed Column) 22 3F527 Lever Assembly (Manual Transmission) 23 3F530 Pin (Manual Transmission) 24 3F752 Brake Shift Interlock Solenoid 25 7335 Gearshift Lever Socket Bushing 26 7A216 Transmission Shift Selector Position Insert 27 7302 Transmission Selector Lever Arm and Support 28 7E395 Shift Cable and Bracket 29 7210 Gearshift Lever 30 3E691 Steering Column Shift Lock Pawl 31 7W441 Gearshift Lever Pin 32 3676 Steering Column Instrument Panel Bracket 33 3D681 Steering Column Lower Bearing Retainer 34 3517 Steering Column Bearing Sleeve 35 3L539 Steering Column Bearing Tolerance Ring 36 3C674 Steering Column Lower Bearing Spring 37 3C131 Sensor Ring 38 3518 Steering Column Bearing 39 N806423-S56 Steering Column Retaining Nuts 40 14A163 Wiring Harness Retainer 41 3F723 Steering Actuator Housing 42 3B663 Steering Column Lock Lever Pin 43 11572 Ignition Switch 44 3D655 Steering Column Position Spring 45 3D653 Steering Column Locking Lever (LH) 46 3B768 Steering Column Position Lock Spring 47 3B662 Steering Column Locking Lever (RH) 48 3E715 Lower Steering Column Lock Actuator 49 3E696 Steering Column Lock Spring 50 3E691 Steering Column Shaft Lock Pawl 51 3E723 Upper Steering Column Lock Lever Actuator 52 3E695 Steering Column Lock Cam 53 3D656 Steering Column Tilt Flange Bumper 54 14A163 Wiring Harness Retainer 55 391727-S304 Shroud Screws 56 3530 Steering Column Shroud 57 3E717 Steering Column Lock Gear 58 3E700 Steering Column Lock Housing Bearing 59 3C610 Bearing Retainer 60 11582 Ignition Switch Lock Cylinder 61 3L539 Steering Column Tolerance Ring 62 3520 Steering Column Upper Bearing Spring 63 3C610 Snap Ring

on the positive side battery cable their is a small wire coming off cable end, is a fuse connector an the fuse is bad .

Could be a coincidence, as they are NOT on the same circuit. If you have no speeds, could be,fuse, relay, resistor, or blower motor. As for turn signals, do the 4-ways work? If so your flasher is okay, May be the switch on the steering column

Okay first check your fuses ensure I turn on the headlights and the... they are good. Otherwise most lights are dim through the turn signals switch. Especially with tilt wheel over time due to the use of the tilt wheel the wires Bend and break you will need to gain access to the steering column by removing the panel to the steering column a test-light will determine where power starts and ends.