I've used this one. https://www.amazon.com/gp/product/B07NF6JQQ4
don't have external drive that big
Merely copy your Windows files to a NTFS drive volume. Not sure of your internet speed, but uploading 400GB would likely be very slow.
drive options though you don't give your physical location or any other useful info:
$60 at Amazon.com WD 2TB Elements Portable External Hard Drive HDD, USB 3.0, Compatible with PC, Mac, PS4 & Xbox - WDBU6Y0020BBK-WESN
$110 at Amazon.com SAMSUNG 870 EVO 1TB 2.5 Inch SATA III Internal SSD (MZ-77E1T0B/AM) with a USB adapter if needed.
If you buy these $40 parts from Amazon and only load your most intensive multiplayer games on it, it will totally change load times and framerate to be better.
Kingston 240GB A400 SATA 3 2.5" Internal SSD SA400S37/240G - HDD Replacement for Increase Performance https://www.amazon.com/dp/B01N5IB20Q/ref=cm_sw_r_apan_glt_fabc_ZD62H0XAD94X5QHM1G44?psc=1
SABRENT 2.5-Inch SATA to USB 3.0 Tool-Free Clear External Hard Drive Enclosure [Optimized for SSD, Supports UASP SATA III] (EC-OCUB) https://www.amazon.com/dp/B07NF6JQQ4/ref=cm_sw_r_apan_glt_fabc_YG73J5AJWK3G9ZWN4K0T?psc=1