Hi @MKU,
You can use the current installation with x-pack features disabled.
In case, in future, if you need to use x-pack features you would not need to install anything else and just enable the features that you want to use with an appropriate license. With the basic license, you get some additional features like Index lifecycle management, Data rollups etc. For comparison please see here https://www.elastic.co/subscriptions
In case you want an Apache 2.0 OSS distribution and you can download it here: https://www.elastic.co/downloads/elasticsearch-oss
Hope this helps.
Regards,
Yogesh Gaikwad