It might help if you identified the resort, but from your description, I assume it is Scuba Club Cozumel. I doubt if you could find a better, safer place for shore diving in Cozumel. While your dive count indicates you may have little experience, you are the only one who must decide whether you are ready or not. The requirement to deal with boats in SCC shore dive area is minimal as no other dive op can use their dock. There may be the occasional (rare) fishing boat but they are just not that difficult to deal with. You will not need a SMB if you stay in the SCC marked area. It is fairly easily navigated with a number of entry and exit options. There is plenty of life to see even though you will not find corals other than very small fist sized growths. The rubble from their destroyed dock as well as other man made attractions and grasses will give you hours of enjoyable critter hunting. And, unlike Cozumel boat dive, if you would like to spend 30 minutes watching a Chain Moray hunt in the rock rubble, you are free to do so, especially if you are solo. Depths will be in the 15 to 25 ft range so a CESA, if required, would be little challenge. Even their 63 cu ft tanks should last you an hour or more in such a shallow, easy dive. Currents are usually mild out of the south but do be watchful for stronger (still quite managable) currents that may alter your dive plan. And, you will find plenty of other divers doing the same thing so you should have no trouble picking up a buddy if that is the route you decide to take. It is also a great opportunity for night dives so bring a couple lights and take advantage of that. The DM (guide) for your first shore dive is a good idea. You will want a compass and then you can use it, and an UW writing tablet to record way points, headings, and distances.
Enjoy