HELP! Macbook Pro 2015, 128 SSD 8GB ram. Creating proxies to avoid choppy footage editing, however going low on disk storage.

Hey guys, so I am using Macbook Pro retina early 2015. Specs: 128 SSD, 2.7 GHz Intel Core i5, 8 GB 1867 MHz DDR3, Intel Iris Graphics 6100 1536 MB.

I know the computer is not for editing, thats why I start using proxy to avoid that choppy 2.7k footage. However, the second problem is the SSD space, I have only 128GB, wheres around 60GB free, when I wanted to start editing, create those proxies, I have run out of space, even tho I haven't upload so much, as it duplicates all the footage.

So I've bought an portable external drive WD elements 1TB few days ago, its not an SSD, as they are super expensive, my question is..what would you suggest me to do as starter video editor. Is it okey to use my project folder in that WD external drive, including with Proxies folder? And the media that Im going to use for the project to keep in WD external drive as well?

Or better is to keep the media (footage) in the external drive and use/keep/save Proxies and other project data in my macbook SSD drive? to increase the work speed?

I just basically dont want to run out of storage on mac as I dont have much of free space, my free space is 60GB and footage is around 40GB plus proxies will duplicate the footage..

Or you think I can keep everything in external drive and hope that It wont crash in the middle of the work with loosing all the date as it has some previous footage from my past years..

Please help! thanks a lot for reading all this guys! appreciate!