public async Task<DTOUser> CreateUser(DTORegister source)
{
    var result = new DTOUser();

    try
    {
        var user = new DTOUser()
        {
            Active = (int)defaultNumber.One,
            Deleted = (int)defaultNumber.Zero,
            DateCreated = DateTime.Now,
        };

        result = await Task.Run(() =>_RepositoryUser.Add<DTOUser, DTOUser>(user));

        //This part is where I dont feel confident
        var login = new DTOLogin()
        {
            Email = source.Email,
            Password = source.Password,
            OwnerID = result.UserID, //using the result of my 1st task here.
            DateCreated = DateTime.Now

        };
        //use the login object to my 2nd task
        var task2 = await Task.Run(() =>_RepositoryLogIn.Add<DTOLogin, DTOLogin>(login));

        result.IsSuccessful = true;

    }
    catch (Exception ex)
    {
        result.ErrorMsg = "BL Error - " + ex.Message;
        result.IsSuccessful = false;
    }
    return result;
}

public TOutPut Add<TOutPut, TInput>(TInput input)
        {
            var entityObj = MappingConfiguration.MapObjects<TInput, TType>(input); //Calling my automapper method to map my Entity object and DTO Object
            _entity.AddObject(this.GetEntitySetName(typeof(TType).Name), entityObj);
            _entity.SaveChanges();
            return MappingConfiguration.MapObjects<TType, TOutPut>(entityObj);

        }

result = await Task.Run(() =>_RepositoryUser.Add<DTOUser, DTOUser>(user));

//use the login object to my 2nd task
var task2 = await Task.Run(() =>_RepositoryLogIn.Add<DTOLogin, DTOLogin>(login));

public async Task<DTOUser> CreateUserAsync(DTORegister source)
{
    var result = new DTOUser();

    try
    {
        var user = new DTOUser()
        {
            Active = (int)defaultNumber.One,
            Deleted = (int)defaultNumber.Zero,
            DateCreated = DateTime.Now,
        };

        result = await _RepositoryUser.AddAsync<DTOUser, DTOUser>(user).ConfigureAwait(false);

        //This part is where I dont feel confident
        var login = new DTOLogin()
        {
            Email = source.Email,
            Password = source.Password,
            OwnerID = result.UserID, //using the result of my 1st task here.
            DateCreated = DateTime.Now

        };

        await _RepositoryLogIn.AddAsync<DTOLogin, DTOLogin>(login).ConfigureAwait(false);

        result.IsSuccessful = true;

    }
    catch (Exception ex)
    {
        result.ErrorMsg = "BL Error - " + ex.Message;
        result.IsSuccessful = false;
    }
    return result;
}