HOW DO I MASK A LOGO TO EDIT PARTS SEPARATELY

[Logan Lukow]

I have a logo that I want to edit different parts separately.  In the image below, I want to leave the green hills with the black undercuts alone, but I want to change the text underneath to white.  I can't seem to figure out how to do this.  I know this may be pud for someone who is experienced, but this is only day one for me on this program, with no prior photo editing experience.  Any help is greatly appreciated.

[HuniSenpai]

First question, did someone give you this composition as, for instance, a .png or something, or did you create this on your own and thus have all of the various layers intact and whatnot? Put simply, does your layers panel look something like this, or is it just Background Layer?

If you do have unique and individual layers like that, my second question is if the text layers have that A for the layer icon? If so, you can use to text tool (t) to go back and modify them. 

[Logan Lukow]

1 hour ago, HuniSenpai said:

First question, did someone give you this composition as, for instance, a .png or something, or did you create this on your own and thus have all of the various layers intact and whatnot? Put simply, does your layers panel look something like this, or is it just Background Layer?

If you do have unique and individual layers like that, my second question is if the text layers have that A for the layer icon? If so, you can use to text tool (t) to go back and modify them. 

It is just a background layer.

[HuniSenpai]

So I'm going to assume that they didn't just send you a screen shot of the logo with the checkerboard pattern, and instead I'm going to assume that they gave you the actual .png file with the transparency on it.

 

Tip: If you don't have the same square selection tool as me (say it looks like a lasso or maybe a circle or something), just keep press m on your keyboard until you get the tool I use, the square marquee tool. 

 

In case you're wondering, what I did in the video was just cut (so delete and put on clipboard) the stuff you want to turn white, and then pasted what was on my clipboard. When you paste in Affinity Photo (and also photoshop, for that matter) it pastes it onto a new layer. When you do an effect like color overlay (BTW, you can do other effects with this process; you could do just an outline to the bottom text, for instance), the effect only affects the layer you have selected. As such, you're only affecting one layer, and that layer only contains what you want to affect which, in this case, is the text at the bottom.