To create the simple glowing text you need text mesh pro. It's available in Asset Store as well as in Unity Package manager.
Inside Unity, go to Window > Package Manager and search for text mesh pro.
Now go to Game Object > 3D Object > Text Mesh Pro Text
Now enter whatever text you want and select distance field shader in text mesh pro inspector tab. See image below.
Once selected you'll be able to see a number of settings under shader and can enable glow from there. I'd recommend playing with numbers here to suit your scene.
Now that you have your glowing text if you want more you'll notice they seem to be using the same shader which will cause a problem if you want glow signs in different colours. For this, we need to create a duplicate of the font asset we are using and use different font asset for different text signs.
Under the text mesh pro settings you'll find Text Mesh Pro(Script) under that you'll find font asset.
You can either duplicate a previous font asset or create a new one using a different font. To create a font asset go to Window > Text Mesh Pro > Font Asset Creator.
Under Font Asset Creator tab select source font file and generate atlas and don't forget to click on Save Font asset under that.
Once the font asset is created you can switch Font Asset in Text Mesh Pro settings and that will use the shader associated with this font asset.
Just make sure you use a different font asset for every glow text of different shade.