In this resistance war without smoke of gunpowder, whether it is the "soldiers" in the front line or the masses of self-control, the whole country overcome the difficulties. 

1. 红色的 it is 错误。it is 指什么？

2. 介词 in 错误，改为 on；介词 of  改为 with。

3. whether...or ...让步从句，跟主句 the whole country overcome the difficulties，没有任何转折关系！十分错误！ 本句不能使用whether...or...，应改为：both...and...have made great efforts.

4. overcome 时态错误。改为完成时。

更为可笑的是，网上很多范文写成“抗日战争”，简直是胡扯：

In this resistance war without smoke of gunpowder, whether it is the "soldiers" in the front line or the masses of self-control, the whole country, the whole people's Anti Japanese War, overcome the difficulties.

修改如下：

In this resistance war without smoke of gunpowder, both the "soldiers" on the front line and the masses with self-control have made great efforts,so that the whole nation have overcome all the difficulties.