Mailchimp, SurveyMonkey and Google Forms are the easiest places to start. Think about running a smaller survey to understand, if the results give the picture, you are looking for - and scale after the initial testrun(s). And make sure, that the platform supports an export format, that you are happy with, when you need to process the responses of the survey.

Scaling it can be done in multiple ways. You can do it organically by posting your survey on online platforms (Facebook, Instagram, Reddit, etc. etc.) depending on where you believe your audience is. You can find a number of groups, where you can post the survey. Or you can buy marketing of the survey, if you can afford it. Or give prices to participants.

But if you want a lot of participants, you have to make it a topic that generally interests a lot of people, and you need some good introductory copy to convert the interested audience to participants. Be honest about your intention; if it is a survey for lead generation, say so.

No way around promotion - either paid, or through the grind of posting and expanding yourself.

Always happy to set up a call, if you want to discuss further options.

Best of luck and best regards
Kenneth Wolstrup