How to copy one list to another list using linq?

Question

Hi All I have two class

public partial class UserMaster
{
        public Guid UserId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Email { get; set; }
        public int RoleId { get; set; }
        public bool Status { get; set; }
        public string PasswordSalt { get; set; }
        public string PasswordHash { get; set; }
        public DateTime CreatedDate { get; set; }
}

 And

public class RMangerViewModel
{
        public Guid UserId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
}

 Basically Manager is from UsereMaster but identify by RoleId=3.

I need to fill  RMangerViewModel  from UserMaster where RoleId = 3 using linq.

Note: List of UserMaster will be fill up by _context.UserMaster.