Hi Manoj,
This is because S/4 only has single client so you need to create a client from HANA Studio to get this "New Entry Button"-
1) Login to HANA Studio using SAP Schema user (SAPABAP1 or SAP<SID> (in case you changed the Schema during installation))
2) Launch SQL Prompt and execute below query-
INSERT into SAP<SID>.T000 (MANDT, MTEXT, LOGSYS) VALUES ('100', 'INDIA', 'SIDCLNT100')
3) Login to SAP and execute SE11 Tcode and activate dictionary.
4) Verify SCC4 and you will have the new entries button.
Saurabh Mishra