Cooley he's a generational talent, and could end up being the greatest ever English player. He appears to have got everything; height, physique, fitness, technique, turn of pace, football IQ, non football IQ and both on field & off field temperament.
I don't think that he's robust enough for the long term rigors of the PL, but due to his Birmingham City education & early exposure to english style/championship football, he puts it about enough in Spain/international football to qualify as robust. His header last night was very brave for a modern stylish player.
I rated Gascoigne at the same level as a player (although different types of player) between 88 - 91, and then it fell apart. He was 23 or 24 in 90 for the WC and didn't look out of place. All in all he played 57 times for England and scored 10. Bellingham is a Gnat's cock off 21, and he's already played 30 times and scored 4, and looks the part already at the EC.
I think that he'll be to England like Messi is to Argentina. An icon for the national side, but won't play in the domestic top flight. Mbappe has signed a 5 yr deal at RM, and there's rumours of Haaland already agreeing something, so i doubt that Bellingham will move anywhere in that period of time, and when you look at Ramos (16 yrs at RM), Modric (12 yrs at RM), Kroos (10 yrs at RM), and Ronaldo (9 yrs at RM), RM keep hold their talent for the majority of the peak of their careers. I could then see him doing 3 years in MLS.
@Flaneur nails his only slight weakness, because he's had the majority of his footballing education in germany & spain, and because he's Real Madrid, he has developed the trick of taking the slightest touch from an opposition player and stopping play and throwing his arms up to get the decision, and control the Ref.
It'll be interesting to see if he gets distracted by off field interests in the next couple of years, as I think that his Mum has a fairly tight grip of his business affairs and it's worked very well so far. I think you are looking at someone who ticks a lot of boxes commercially, and I wouldn't be surprised if you see Adidas/Nike/Puma signing him up to a life time deal. He has the talent of a Jordan and the marketability of a Beckham.