Is it intentional, that you posted the same link as in your previous message? Because /e/ does not officially support the LeEco LE2 PRO X620.
Here is an ebay link for supported LeEco Le2 devices: https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR1.TRC0.A0.H0.Xleeco+le2+x526.TRS1&_nkw=leeco+le2+x526&_sacat=0
(Make sure, that you find one of the supported device model numbers X520, X522, X526 or X527 in the description)
Current status is that the e.foundation does not sell preinstalled devices yet.
But according to this recent announcement it looks like the Fairphone FP2 is a candidate for the first preinstalled device, that will be sold:
Currently the only way to get /e/ on a phone is by flashing it oneself. For example you find instructions of how to flash the LeEco Le2 here: https://gitlab.e.foundation/e/wiki/en/wikis/device/s2/install
You can find Installation instructions for the other supported device on this page: https://gitlab.e.foundation/e/wiki/en/wikis/devices-list