According to some speculations Manchester United were also having some interest in Bellingham but they decided not to go for him after seeing that many other big teams also entered the race to sign him.
This is a wise thinking for them because they wouldn't really stand any chance against teams like Real Madrid and Liverpool especially. I know that Liverpool are technically below them in the league standings currently. But they have still been a much more successful team than Manchester United in the recent years. They have a much more capable squad at the same time. Apart from that Real Madrid are actually ahead of both of them now. Because Real Madrid is always a dream for this kind of talented youngsters. They were very successful in the previous season also and they are the same for now.
Real Madrid are building another squad full of future stars. Bellingham is already impressive of course and he can have a really unforgettable career there.