Op the one concern I have for you, having read through your thread with care, is that it is plainly obvious from the outside looking in so to speak that you are not giving your age and your ability to have children enough focus.
You say you are confused and have circular thoughts when it comes to starting a family, and I may be more direct. You really don't have all the time in the world to make up your mind. This is something that is rather more pressing than your next career - and needs far more thought.
If by your current time frame and plan you intend to make the leap in 2023 you will then be 37. It may be too late to meet someone else and start a family, and even if you started immediately you would likely run into problems as you enter your forties.
Of course your intellectual and career pursuits are important, essential even, but in focusing overly on that area you may lose the chance altogether of having a family. Which may suit you entirely, or you may live to regret it depending on your nature and ambitions.
From what I have read you really don't want to have children where you are now, and it sounds like you have doubts even about the man you are with in terms of such a big commitment. Running a bar is not conducive with family life, you will end up doing all of the parenting alone, and far from home and family. I sense you know what on some level.
Moving to another France would lead to a similar set up potentially with another man. So unless you are set on marrying a French man and living there forever, then this won't end well in terms of settling down in the longer term. You are putting off the inevitable.
I have many friends that married men from different countries, it really is not for the faint hearted op. They often have very different values, ideals and parenting. Many of my friends consider themselves 'trapped' with very young children and no way to move home. I would be very, very careful. I accept culturally France is similar in terms of values, but until you are in that position you won't really know what kind of father he will be, nor how family interference/support is natural and normal for them. It could be vastly different from what you want, and will it be easy to legally go home with a baby that was born elsewhere.
I would shelve the training, and focus on the bigger picture. The reason why you are confused really is because you are jumbling up too many aspects. Break it down - simply put:
Do you want children with dp?
Do you want to stay there for good or at least until your children are adults?
Is he going to make a good father?
What options are there for your career in the future?
Start there, is he the right man yes or no and then move outwards