This is a difficult question to answer because there is no one-size-fits-all answer. The amount of time it takes to raise pre-seed funding can vary greatly depending on the startup, the industry, the amount of money being raised, and a number of other factors.
That being said, the average time it takes to raise pre-seed funding is 3-6 months. However, it's not uncommon for startups to take longer or shorter amounts of time to raise this type of funding.
If you're looking to raise pre-seed funding, the best thing you can do is to start networking with potential investors and pitching your startup idea. The more people you talk to, the better your chances of finding someone who is interested in investing in your business.
Here are a few articles that might be helpful as you start the process of raising pre-seed funding:
https://www.forbes.com/sites/alejandrocremades/2017/12/11/pitching-for-pre-seed-funding-7-tips-for-startups/#1d43687562f9
https://www.the startup garage.com/blog/how-to-raise-seed-funding
https://www.entrepreneur.com/article/292627