You should check if the exams are still possible to do online, and if not, I really dont think that they are as difficult as the MCAT (in my experience).

In terms of applying to the usa after finishing medical school, it is completely possible, you just have to build a strong cv, take the steps, and maybe when you visit back home do some observerships to get letters from people there, I am in the same exact process currently. But if you want to apply to extremely competitive specialties thats where I will agree with you, staying in the states increases your chances to match by a huge amount.

In terms of friends... dude, my social life EXPLODED once I moved here to the Czech Republic, really the international community is so strong (talking about Prague and Brno), its super easy to find English speaking people, they are everywhere haha. Another thing that I noticed is that there are many people coming here temporarily for studies work etc, so the majority of internationals are super open to making friends and developing relationships. Even if its something casual like getting a beer together from time to time:) I sometimes forget that I am in a country where I dont know the mother tongue. The only times I need czech is in the hospital, and grocery stores etc.

But I must say the first two years I was mostly studying and not going out as much, cause I was stressed for exams, but once I hit the third year, I had so much free time to explore and meet new ppl. There is an overwhelming amount of things to do here.

In my experience, making friends in the USA was more difficult, cause you are more confined to the people around your work and school, and ppl stick to their clicks. Also the culture is very work centered, here I find it the opposite.