How to make 1000$ investment with only 100$

Yes it is correct that you can make 1000$ investment with 100$.
now you are thinking that how it can be possible? but it is.
i.e., leverage which is offered by many brokers like www.etoro.com.
I mention this site because I am using this site for 2 years.
it is a trusted site with so many satisfied users.

now you are thinking that what is leverage
No worry

Leverage is the use of various financial instruments or borrowed capital, such as margin, to increase the potential return of an investment.
2. The amount of debt used to finance a firm's assets. A firm with significantly more debt than equity is considered to be highly leveraged.
Leverage is most commonly used in real estate transactions through the use of mortgages to purchase a home.

now consider it mathematically
suppose you have 100$ broker provides leverage of 2,5,10 etc for share trading and investment.
for forex it provides 2 to 400
if you buy shares of Microsoft for 100$ using leverage of 2 it buy shares value of 200$
it means
using leverage of 5 you can buy shares of 5*100=500$
leverage of 10 share value you buy 10*100=1000

so earn money and become rich.