Fill inn gaps in data of multiple regression model

General
,
2

I think you actually mean to interpolate between values, there are many ways of doing this. I let you some examples in the link below.

https://www.tutorialspoint.com/how-to-replace-missing-values-with-linear-interpolation-method-in-an-r-vector

If you need more specific help, please provide a proper REPRoducible EXample (reprex) illustrating your issue.