For me with my country's low currency condition I think its possible because the bitcoin price is very expensive, for example; a policeman with the lowest rank in my country is paid around 0.1 btc. So can we get 0.1 btc each month? I think yes, isn't it ?
But I think if you can do it both its better for you.

only try to earn bitcoin and dont work anything anymore is too risk. we dont known what will happen in crypto world so have a job is the best way to protect your future

Relying solely on bitcoins as a source of income is not really a good idea, with the trading of bitcoins, the value can take a dive at any moment and it may affect the money that you may be earning in the process, I suggest that you have a good job and then do the bitcoin business on a part time basis. There is nothing wrong with earning money on both sides.

But the difference is:
That policeman is getting healthcare, he has unemployment benefits, he will get a pension.

On the other hand, you have none of those.
And in western countries without healthcare insurance you're done if something happens.
A simple set of blood liver and kidney analyses and diagnostics would have emptied my wallet by 150 euros this month.
With insurance it was only around 30.

You're right, but nothing is steady in your life either. You might think it is because your boss gave you a signed contract, your money is lying safe in a bank, you have steady income and the currency hasn't changed its value in years, but it's all a house of cards. You can get kicked out of your job for a simple mistake tomorrow, or they can go bankrupt in a week and leave you with no income. The bank can go bankrupt, or it can freeze your money because of a crisis. You never know.

I prefer that you get your day job while working here in this forum for a campaign so you can get an extra income, But if you want to know if working or trading here is enough for living ? then i prefer that you should join signature campaigns rather than trading because the pay outs is quiet high and with good budgeting then you can obviously survive in a month.

Earning enough bitcoins to make a living depends on how much money you need to make a living.
And it depends as well on how much money you have available to make investments.
I think that a well paid signature campaign can bring more money a day than a worker in a third world country earns in ten hours.

And if somebody lives in an industry nation, he has the option to do tradings. Bitcoin moves a few percent against most altcoins each day.
Let's say somebody is capable to get a profit of 0.5% every day. With a trading volume of 6 bitcoins he could make 100$ each day.

I know many people living only from trading. It's enough only if you find your way to real money not thousands of Satoshis.

It took a long time to build communication that is worth a darn, but I am earning Bitcoin for a living, and steadily.  It will continue to grow in size as time moves along too.  We are all lucky enough to be in the seedling stages of Bitcoin's lifespan.  We can be wealthy with time.