I am aware that to unsubscribe from UE4 I will lose many features such as updates, support in case of problems and more importantly the right to ship my game, but I’m only interested in having the software to learn and practice as I prepare to develop my games more seriously
And in case I can do this, can I go back for the subscription and ship a game that I did in the whole time I was unsubscribe?
When you are looking to ship a game, you do not need to re-subscribe either, the only thing you loose without a subscription is access to GitHub, and the ability to download the latest versions. Also you will not lose support at all, you are still able to get the same service as with a subscription.
For more details on this, please check out the licencing section of the FAQ available here: