Just a quick glance here:
- Did you go Worker first? you're late on improvements and the city should be size 3 already at T25, where you can start a settler. Improve the Corn, grow on a FP at size 2. Farm a FP then camp the Ivory, it's essentially a Grassland Hill when improved.. Work the Ivory at 3 when building a settler. Grow there first.
-Why have you not farmed one of the FP yet?
Germany starts with Mining and you teched Agri for the corn; assuming worker first you have 18 worker turns to use by T33; farming the corn then camp in that order is 10 worker turns done by T24. You have enough to still move to and Farm a FP before this turn. It appears you either Farmed the corn second or have just moved back to farm that grassland from the Ivory, but you should be doing the FP if you want a farm -- they not only give more food, but being riverside, an extra commerce too. They are actually 5 yield tiles. All those riverside grass hills are nice to for slow building if mined.
Cottaging is important but try to think food or at least Settler/Worker output first, at least for the first turns with the capitol. So in a situation like this where it's between save the FPs for cottages by farming weaker tiles, or or farm the FPs, I'd farm at least one first then replace later. The grass river hills can be okay too but generally FOOD is best, especially when you don't have multiple resource starts.
Actually looking at the overview, I would have settled ON the Ivory. No need to improve it, extra hammer, you can still grab the fish and crab spots, you could then settle a city on one of the Plains Hills and share the corn + some cottages. The middle fish is a trap; you're not gonna get it without a border pop and it can be reached from that western island/landmass anyway.
In terms of game plan though, should I run GP farm seeing that I have Germany?
Just because you are PHI doesn't mean you have to go right out for a singular GP farm. It will speed natural generation from Libraries in many cities as well, so any potential spot with at least a +4 food tile can farm scientists for you. Just try to get the libraries and run the scientists near around the same time, and they'll come roughly 9 turns apart in the different cities. Alternatively, you can just grow as large as possible, wait for a golden age + pacifism + caste, and run as many as possible (starving the cities) to get them out all at once.
For a GP farm you'll want a spot with preferably a lot of food surplus in as few tiles as possible; a better spot for that just in this glance is the spot that can grab BOTH fish and run a lighthouse for 2 +6 food tiles. National Epic is also really nice for that type of city but is a pain without Marble. it's hard to make the evaluation so early when there's more of the map to find out. And since that would require border pops for decent food, it's not a good early city either.
The point is, that's getting ahead of things. You'll probably want to see how the religion plays out and whether you can get marble or not before deciding on running one large GP farm. You've got good cottage potential with a river capital, there's no reason to ignore that.