I wouldn't use GoDaddy. Literally anything else is better. Their UI is so confusing and I'm just not a fan. I'm a big fan of Google Domains, but Namecheap and a few others look promising, too. I really like DomainHolder too. It makes a for sale page for your domain. Literally all you have to do is make an A record to their domain and TXT record with your email where potentials buyers can contact you.

Much of the domain flipping business just involves patience. Chances are if you buy a domain and then immediately reach out to the brand you are talking about, they won't be interested because you just bought it, and they probably would have bought it before you but they didn't because they weren't interested. Having a domain in your portfolio for 5-10+ years increases the chances of it being inquired about because the number of decent domain names is drastically decreasing. It took me a few hours to find a domain name for a side project I'm working on, they aren't many good ones left :)

I don't think the registrar matters that much as you will likely end up transferring the domain to the buyer's registrar anyway. If they do happen to use the same registrar then you can often use an "internal push" which is faster than transferring across different registrar, but you probably don't know which registrar the buyer will have, plus it's typically a minor issue anyway. So no, the registrar you use doesn't matter with regards to selling a domain. (There are some other questions about which registrars people prefer. I use Namecheap.)

As for the chances of hitting a deal: I often see people getting into this market and buying a ton of crappy domains thinking people will be interested. If they are available for registration though, chances are nobody wants them.

There are some exceptions, specifically when it comes to recently dropped domains (i.e. those that were registered before, but not renewed), and domains that relate to things that have suddenly become popular whereas they weren't before. (e.g. bitcoin a few years ago).

I would stay away from registering domains that contain a brand. This is known as domain squatting and is potentially illegal. There's a decent chance that if the brand owner wants to actually have the domain they can get it from you through legal matters.

IMO the best way to make money in this business is informing yourself about specific markets and buy relevant domains you think will grow in value over time. For example if you think augmented reality (AR) will become a hit then it would make sense to buy some domains for that. Although for that particular topic you might already have missed the both.

P.S.
It seems like you're interested in domain flipping (buying and selling for profit) rather than domain reselling (allow other people to buy domains through you as if you were a domain registrar) so I've changed the question title accordingly.