It is not surprising, with all the scams that happen online, that people are wary when they are looking for ways to earn. It is in fact very wise to be wary as you could find that you get into problems if you do not. You want to be sure that you will be paid for the work that you are doing and that you are not going to be scammed.
The first thing that you should do is negotiate to be paid through Paypal. This will protect you against having to reveal your bank details and so you know that you will not get into trouble by anyone knowing these. They could use them to sign your account up to direct debits, for identity theft or even for other types of fraud.
You also need to make sure that you can trust them to pay you. Most online work is not done formerly with a contract, just through email agreements or terms on a website. This is much more informal and if you do not get paid it is very hard to get your money out of the person. They may not even live in the same country as you and could have provided false information. One way to protect yourself is to ask for some or all of the money up front and then you know that you will already have your earnings for the work that you have agreed to do.
If it is a company that you are working for then they are less likely to agree to pay you in advance. However, they are more likely to have had quite a few others work for them before you. Therefore you will be able to do some online research and find out what other people think of them. You might find this sort of information on money making websites, blogs, forums and message boards as well as social media groups and pages.
Making money fast is something which may not be so easy. You will need to spend some time looking into how to earn money and where you can make it to be sure that you will be paid. You may then find that some websites will only pay you once you have accumulated a certain amount of money and that may take time to build up. This is fine if you are happy to wait to be paid but if you need the money quickly then it may be better to not do these.
You may also find that the work will not pay that highly. There is a lot of competition for online work and so that means that the employers do not have to offer a lot of money in order to find workers. Many workers will come from other countries where the standard of living is lower and so they will not need such a high pay and the employer may also come from a country with a lower standard of living and may not be able to afford to pay that much money.