Left low beam of my A4 model 2011 is very low, how can I adjust to higher level

here's your answer for the low beam..

https://www.justanswer.com/mazda/58sx8-mazda-adjust-headlights-low-beam-needs-higher.html
just make sure to have the vehicle somewhere where the headlights reflect off wall/garage door with the vehicle about 15-20 feet away so you don't go too high if that's the direction you want to go. and end up blinding oncoming traffic.
hope this helps you.

How to Adjust Car Headlights Level your car. Start by removing any excess weight from the trunk of the car. Also, ensure that the tire pressure in all tires is at the manufacturer's recommended levels. If possible, have somebody sit in the driver's seat, and that the gas tank is half-full. As well as this, check that your headlight aim adjustment wheel (if fitted) is at the zero position. Position your car. On level ground, park 10 to 15 feet (3.0 to 4.6 m) from a dark wall or garage door, with the front of the car aimed at the wall. A paved parking lot or level driveway is best Turn the headlights on. Do not use your high beams or fog lights. Mark the horizontal and vertical center lines of the headlight beams with masking tape to make two T's on the wall or garage door.Make sure the lights are level. Place a carpenter's level between the two marked center lines to see if they are even. If they are not even, use a tape measure to measure how far up the wall the lower mark is and lower the other center line marker to the same height. These center lines should be no higher than 3.5 feet (1.1 m) from the ground.Back your car exactly 25 feet (7.6 m) from the wall or garage door. Don't estimate the distance! Use a tape measure to make sure you are the proper distance away from the wall. Turn off the headlights. Remove the trim ring from around the headlights and locate the adjusting screws. These screws are typically found adjacent to the headlight, though some manufacturers put the screws in the engine compartment, behind the the headlights. The horizontal adjuster and the vertical adjuster should be marked.

• Always defer to the specs in the owner's manual-Adjust each headlight separately. Block one with a sweatshirt or other object while adjusting and testing the other, since the light-bleed can make it difficult to distinguish one from the other. Have a helper sit in the driver's seat while you do the adjustments, to turn the lights on and off while you make the proper adjustments

The fuses location for the headlamps on a 1999 Audi 2.8 A4 Quattro are:
F18 (10 A) - RH headlamp - high beam
F19 (10 A) - LH headlamp - high beam
F20 (10 A \ 15A) - RH headlamp - low beam, headlamp adjustment
F21 (10 A \ 15A) - LH headlamp - low beam, headlamp adjustment

For Audi A4 the fuse box is located on the left side of dashboard behind a plastic cover (for left hand steering wheel vehicle). On inner face of the plastic cover you will find the fuse diagram.

You can't adjust beam strength - can only adjust hight by using
adjustment screw on lamp assembly underhood

For Audi A4 the fuse box is located on the left side of dashboard behind a plastic cover (for left hand steering wheel vehicle). On inner face of the plastic cover you will find the fuse diagram.
First fuse on first row from left upper corner is Fuse Nr.20 = F20 (15A) - RH headlamp low beam, headlamp adjustment.
First fuse on second row from left upper corner is Fuse Nr.21 = F21 (15A) - LH headlamp low beam, headlamp adjustment.

For Audi A4 the fuse box is located on the left side of dashboard behind a plastic cover (for left hand steering wheel vehicle). On inner face of the plastic cover you will find the fuse diagram.
First fuse on first row from left upper corner is Fuse Nr.20 = F20 (15A) - RH headlamp low beam, headlamp adjustment.
First fuse on second row from left upper corner is Fuse Nr.21 = F21 (15A) - LH headlamp low beam, headlamp adjustment.

There are two adjustment points (screws). For example left headlight: you will see one point near the end of left wing, at bottom side through a wing hole. This is for vertical plane headlight beam adjustment (up-down). Another one point is against water radiator side. This is for horizontal plane headlight beam adjustment (left-right).

The adjustment screws/nuts should be located either on the top of the headlamp assembly, behind the headlamp assembly, or near the frame rail by the radiator support.

You will have vertical adjustment screws for each independent beam (separate highs and separate lows, but will be same screw if highs and lows are the same bulb). You may also have additional horizontal adjustment screws as well

Park your car on a level ground 30 feet from a wall and measure the height from the ground to the bulb and mark on a wall (do this for highs beams and low beams if the bulbs are separate, if highs and lows are the same bulb, only do it for the lows)

If the headlights read VOR, then aim the brightest part or cutoff part just below the mark on the wall. If it says VOL or nothing, aim them 2 inches below the mark on the wall.

The adjustment screws/nuts should be located either on the top of the headlamp assembly, behind the headlamp assembly, or near the frame rail by the radiator support.

You will have vertical adjustment screws for each independent beam (separate highs and separate lows, but will be same screw if highs and lows are the same bulb). You may also have additional horizontal adjustment screws as well

Park your car on a level ground 30 feet from a wall and measure the height from the ground to the bulb and mark on a wall (do this for highs beams and low beams if the bulbs are separate, if highs and lows are the same bulb, only do it for the lows)

For Low Beams: If the headlights read VOR, then aim the brightest part or cutoff part just below the mark on the wall. If it says VOL or nothing, aim them 2 inches below the mark on the wall.

For High Beams (if separate from low beams): Aim the headlight directly at the line you marked on the wall.

Go to mechanic !