So it's complicated and not entirely clear how connected/separate Final Fantasy VII Remake and Compilation of Final Fantasy VII are. The creators have at different times said that they are connected and aren't connected. The in game evidence is inclusive.

Final Fantasy VII Remake is a very much expanded retelling of the Midgar portion of the original Final Fantasy VII. However, there are significant changes and additions made to it. Some characters appear sooner than before. Characters that were in other parts of the Compilation but not the base game were added to Midgar. People live longer than they did in the original. Some characters are alive that were dead at this point. Two of the characters seem to have knowledge of what happened in the original game and know stuff that they shouldn't this early in the story, but it's not conclusive.

They also have added these ghost like creatures that when the characters try to divert from the events of the game too far force the characters to take the game route. The climax of Final Fantasy VII Remake is defeating these beings to free the characters from the previous fates.