As an underweight person you cannot carry that much weight so we are going to focus on carrying our own weight by doing body weight exercises
here are some body weight exercises that you can do!!

PUSHUPS

PUSH UPS

For beginners it is recommended to do wall push ups first for 10 reps and 3 sets, once you have gotten used to that, you can continue to do slanted push ups by using a chair. Lastly you can do regular push ups on the floor for 10 reps 3 sets but if it's easy you can go and increase the number of reps.

SQUATS

When squatting, the movement should occur in your hips, knees and ankles — not the torso. A neutral spine (shoulders pulled down and back, and a steady natural curve of the lumbar spine) should be maintained throughout the entire movement. This is especially true at the bottom of the squat when hips tend to tuck under. Do 10 reps of 3 sets

DIPS

1. Sit on your chair or bench with your arms at your side and your feet flat on the floor, hip distance apart.
2. Position your hands so that your palms are down beside your hips. Your fingers should grip the front of the chair seat.
3. Move your torso forward off the chair with your arms extended. Your buttocks should hover over the floor and your knees should be slightly bent. Your heels should touch the floor a few inches in front of your knees.
4. Breathe in as you slowly lower your body, hinging at the elbows until each forms a 90-degree angle.
5.Breathe out as you push up to your starting position with your arms fully extended.
6.Complete the exercise 10 to 15 times for your first set. Then complete another set. You may work your way up to doing more repetitions or sets of this exercise as you build strength.

SIT UPS

1. Lie down on your back.
2. Bend your legs and place feet firmly on the ground to stabilize your lower body.
3. Cross your hands to opposite shoulders or place them behind your ears, without pulling on your neck.
4. Curl your upper body all the way up toward your knees. Exhale as you lift.
5. Slowly, lower yourself down, returning to your starting point. Inhale as you lower.
Beginners should aim for 10 reps at a time.

PULL UPS

1. Grip the pull-up bar with your hands slightly wider than your shoulders.
2. Face your palms away for a pull-up, and toward you for a chin-up.
3. Pull your shoulder blades down and back, sticking out your chest.
4. Use only your arms and upper body to raise your chin above the bar.
5. Steadily lower yourself until your arms are extended, and repeat.