If this is your first stage of investment and you are asking for under $1 million it is typically called seed capital. If your in America, California - namely Silicon Valley is the best place to raise money for new startups. You will need to have a business plan ready, and probably a working prototype of whatever invention you have to prove it works. Then you will have to convince them that your invention will solve X problem in a market worth $43 billion or whatever.
I have to say its a tough time to be raising money, given that IPOs are dead. Investors only exit strategy is to sell/merge your company with a bigger one. (That is unless you can pay them back plus gains with dividends).
Good luck!
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