can i work on macbook while charging

Yes.

If you're new to Apple laptops, don't micromanage the battery. Charge it when needed and use it on battery when you need to do that. Trust the MacBook's charging circuitry to take care of your battery.

However, the battery is a consumable and will eventually wear out and need replacing. How long that takes is not predictable, but normally you'll get several years usage. My 2016 MacBook Pro 13" still has over 89% of its capacity. Apple recommends batteries be replaced when full charge capacity drops to 80%.

Yes, you will get better performance out of your MacBook if you have it plugged in as opposed to running it of battery power, so I would argue that it is better to run your Mac of the power cord rather than battery.

Yes, in fact if you want to preserve your battery’s life as much as possible, you should leave it plugged in as much as possible. Your MacBook Pro has circuitry to protect the battery from over or undercharging. So you never have to worry about leaving it plugged in too much, or even leaving it unplugged too long.

In fact, the far more important thing is to minimize cycles. A cycle is a full discharge, followed by a full charge. But partial charges and discharges count, so if you use 25% of the battery today and 75% of the battery tomorrow and then charge it to 100%, you would have done 1 cycle in 2 days. So the more you minimize cycles, the longer your battery will last. You minimize cycles by keeping your laptop plugged in as much as possible.

It should be noted the battery will degrade even when plugged in. Nothing can stop a battery from degrading over time. It doesn’t matter if you leave your laptop plugged in, or even if you shut down your laptop, unplug the power cord and don’t use it for a year. The battery will still degrade. It is the rate at which it degrades you are trying to impact. Due to the circuitry in the laptop that protects the battery, keeping it plugged in as much as possible is the best practice for the longest battery life.