1. It looks like Hostgator provides free SSL certs but they expire every 90 days. This would be a pain in the ass for me but you may be ok with updating your certs every 3 months. They have info here https://support.hostgator.com/articles/ssl-certificates/hostgator-free-ssl and it looks like you can manage it with your cPanel. It also looks like they have a premium SSL certificate service which lets you buy certs with 1 & 2 year expirations.
2. You mention that you have subdomains but use one example: hr97.com/ousuxshit. As far as certificates are concerned, this is a single domain. SSL certs only care about the hr97.com part and not about anything after the /. If this is the case, you would only need one SSL cert for hr97.com. If you have other domains or subdomains (like ousux.com or ousux.hr97.com), you will need a certificate for each website.
If you have more than 3 subdomains on a single domain (ousux.hr97.com, www.hr97.com), I would buy a wildcard SSL cert - which would look like *.hr97.com or *.ousux.com. This is the easiest solution but they do charge more for wildcard certs. For instance, a single Gator SSL cert is $40/yr while a wildcard cert is $120/yr - https://support.hostgator.com/articles/domain-validated-ssl-certificates-for-single-domains.
Note: www.hr97.com and hr97.com are different domain names and would need separate SSL certs if you didn't use a wildcard.
Hostgator looks to have decent support for this and they would be able to set you up fairly easily. SSL certs are a common request and any hosting service has experience with them.
Hopefully this helps,