I think dropshipping is better, especially for newbies who have no experience in business as well as marketing. To start a dropshipping business, I'd recommend you read this article: How to Start a Dropshipping Business with Shopify in 2020?.
Hope it helps!
It's a tough call, there are pros and cons to each.
With drop shipping, the positive is that there is no investment in stock needed. The downside is, when drop shipping from a website far away, the shipping could take weeks. When the package arrives it will be from another company so if you are looking for re-occurring customers, giving them a positive experience is something you definitely want to consider.
With buying products in bulk, you have the benefit of offering faster shipping. The downside of course is that you could get stuck with the product if it doesn't sell. I think having at least one of the products in hand is beneficial though because you can take your own photos and do videos for social media and ads and such. It ads a certain level of trust to your brand when you are able to show the product on your website and/or social media channels.
If you decide to do drop shipping, we did a video on how to easily do so using Shopify and Oberlo:
Hope it helps! If you have any questions feel free to reach out to us using the contact information in our signature :).