My iPhone X takes forever to send videos and files

Hi! I don’t why my iphone X takes forever to send videos and files , even when it was new . Small files can be sent easily but even if a file crosses 100 mbs it takes hours to send it . And same with the videos i don’t know why it happens . Can you please help me with this ? What i should do and yes my internet has nothing to do with this it’s same to cellular and wifi networks even other mobiles on the same internet can work properly .

[Re-Titled by Moderator]