Database strategy for concurrent read/write operation in it

I have 6 services talking to the same database SQL Server 2016 (Payments) where some services are doing write operations and some are doing read operations. Database server holds other databases as well than Payments database. We do not have any archival job in place on Payments database. We recently got 99% CPU usage and as well as memory issue on database server.

Obvious steps I can take including

1. Create archival jobs to migrate old data to archived database
2. Can scale up database server.

But still want to explore other best solutions. I have below questions.

1. Can we make different databases for read and write operations, if yes how?
2. Can we migrate data on the fly to NoSql database from RDBMS because it is faster for read operation?
3. What is the best design for such applications where concurrent read and write operations happens?