Can I learn complete Java from here without pc

Answer 1

No, you can learn only basic concepts.

Answer 2

but you can continue combining other resources.

PC is necessary if you learn Java GUI (swing), java frameworks like Spring /Java EE (platform), database connect, tools like maven/gradle, frameworks for testing (JUnit), new features (java 18) and preview features, if you need to use command line options of javac/java, more complex console user input, using of modules, jar files, annotations,
also is best for android development