5g coverage

Recently purchased iphone se 2022 with 5g, was my understanding i would get faster speeds, to me it looks as if i am getting slower speeds, i could sit in a workvan beside someone who has an iphone7 who is on 4g watching videos and i cannot open an internet page, i have always noticed that an iphone 7(some other iphones also) has took presedence over other phones, even with house wifi, even if i am not near anyone my 5g is still slow, how can i fix this, other person is on same network