Want to get linear equation from model output. Also want to get a single coefficient value for a column where multiple lables are there in the eqn

Question

Note(I have used One hot encoding because my data have multiple labels for multiple columns)I have build one linear regression model using R.From the model output I am able to get the linear equation. As my data contains multiple labels for a single column , so I am getting the linear equation for all the lables with coefficients. But I want to get a single coefficient which should be average of all the coefficient or something similar.

My Code:

**Linear Regression:**
#define one-hot encoding function
dummy <- dummyVars(" ~ .", data=mydata)

#perform one-hot encoding on data frame
final_df_supp <- data.frame(predict(dummy, newdata=mydata))
mymodel <- lm(y ~ ., data = mydata)

**Extract linear Equation from Linear Model**
model_equation <- function(model, ...) {
  format_args <- list(...)
  
  model_coeff <- model$coefficients
  format_args$x <- abs(model$coefficients)
  model_coeff_sign <- sign(model_coeff)
  model_coeff_prefix <- case_when(model_coeff_sign == -1 ~ " - ",
                                  model_coeff_sign == 1 ~ " + ",
                                  model_coeff_sign == 0 ~ " + ")
  model_eqn <- paste(strsplit(as.character(model$call$formula), "~")[[2]], # 'y'
                     "=",
                     paste(if_else(model_coeff[1]<0, "- ", ""),
                           do.call(format, format_args)[1],
                           paste(model_coeff_prefix[-1],
                                 do.call(format, format_args)[-1],
                                 " * ",
                                 names(model_coeff[-1]),
                                 sep = "", collapse = ""),
                           sep = ""))
  return(model_eqn)
}

library(MASS)

y = data.frame(model_equation(mymodel , digits = 3, trim = TRUE))

type here

Output: y = 2+0.05x1.a+0.08x1.b+0.3x1.c+3y1.ab+5y1.bc+4y1.cd

data: x1 y1 a ab b bc c cd

I want the output should be : y= 2+0.34x1+6y1