Can I add add custom params to my paypal plan url

[Rendom]

When i'm using paypal button I have this logic 

actions.subscription.create({

plan_id: planId

custom_id: customerCustomEmail,

});

Here I'm also including custom customer email which customer using for my product.

How to do this for dedicated paypal url ? how can I also add custom email with link?

Can I add custom_id param to url like this?

https://www.paypal.com/webapps/billing/plans/subscribe?plan_id=planId&custom_id=customEmail?