Dropbox to iDrive E2 & basic iCloud: Syncing help

Hi all, I currently use Dropbox and have 40GB there and they now want me to pay lots more or they will delete my files. I use a macbook air and have an iphoneSE. Currently my iphone cannot download the latest software as there is not enough space... (using 53.17GB of 64GB). Most of this is in applications. I currently have iphone + for 200GB storage and I apparently use 132.4 of this. I want to cancel dropbox and use something else. Icloud wants £8.99 a month to increase. I was looking at idrive and set up an account but now realise to move things easily I will need an idrive e2 account and pricewise this is ok. However it appears it will not let me sync things like mail and notes etc across my devices. Can someone give me a simple guide to how, if I move to idrive e2 from dropbox (I see varous ways to do this...) how I then can get rid of dropbox completely from everything and how I can move to the basic (free) version of icloud just to sync the necessary stuff? or should I be don't something else instead? I just want quick, simple and for it all to work...... Thanks in advance