To beat Super Mario Bros. Level 1-1, follow these detailed steps:

### Step 1: Start the Level
1. **Begin the Game**: Start Super Mario Bros. and begin playing Level 1-1.
2. **Move Right**: Mario will start moving right. Keep moving right to avoid obstacles and enemies.

### Step 2: Jump Over Holes
3. **Jump Over Holes**: As you move right, you will encounter holes and pits. Jump over these holes to avoid falling into them.
4. **Collect Coins**: If you see a coin block, jump on it to collect the coins inside. This will give you extra points and help you progress.

### Step 3: Encounter Enemies
5. **Encounter Little Goombas**: You will encounter Little Goombas, which are small enemies that can harm Mario. Jump over them to avoid taking damage.
6. **Jump on Goombas**: If you need to kill a Goomba, you can jump on its head. This will defeat the Goomba and give you extra points.

### Step 4: Collect Power-Ups
7. **Collect Power-Ups**:
– **Magic Mushroom**: If you hit a Magic Mushroom, Mario will grow bigger and become invincible for a short time. This can help you navigate through the level more safely.
– **Fire Flower**: If you hit a Fire Flower, Mario will be able to throw fireballs. This can be used to defeat enemies and break certain blocks.

### Step 5: Navigate Through Obstacles
8. **Navigate Through Obstacles**:
– **Pipes**: You will encounter pipes that can lead to secret areas or bonus levels. If you see a pipe, you can enter it to explore these areas.
– **Bricks and Question Mark Blocks**: There are bricks and question mark blocks throughout the level. Question mark blocks contain power-ups or coins, while bricks can be broken to reveal hidden items.

### Step 6: Reach the Flagpole
9. **Reach the Flagpole**:
– **Final Section**: As you approach the end of the level, you will see a staircase leading up to the flagpole. Jump from the staircase to land on the flagpole and complete the level.

### Additional Tips
10. **Timing and Practice**: Timing is crucial in this level. Practice jumping over holes and enemies to improve your skills and speed.
11. **Secret Area**: If you want to skip most of the level, you can enter the secret area by going through the pipe at the end of the first set of pipes. This will lead you to a bonus area with many coins.

By following these steps and tips, you should be able to beat Super Mario Bros. Level 1-1 efficiently.