Sorry for this very basic question from a very early beginner.

I'm trying to analyse survival data of patients treated for liver cancer.

I used survival package to build KM curves, and to make Cox regression (coxph) in R studio 4.2.0

I have two problems: Using Survival package I can't make Cox regression with continuous variable (biomarkers, volume ratio,...); R is calculating a HR in each patient. Then I tried univariate analysis following (Univariate Survival Analysis) but I don't find analyse_survival function, even charging library '"survival". Error message: Error in analyse_survival(vars(Time, Survival)) : could not find function "analyse_survival"

Thank you for your help!

survdiff(formula = Surv(Time, Survival) ~ GTV_HL_ratio)

 coxph(Surv(Time, Survival) ~ GTV_HL_ratio, data = 
 Survival_data_forR_BCLC_gathered) %>%
 gtsummary::tbl_regression(exp = TRUE)