How to display output of 2 commands in ansible?

Question

---
- hosts: all
  gather_facts: false
  user: 
  become: yes

  tasks:

  - name: Checking current kernel on Target Server
    shell: hostname;uname -r
    register: output
  - debug: msg= "{{ output.stdout }}"

Answer 1

Remove the space after "=". Correct syntax is

- debug: msg="{{ output.stdout }}"

, or

- debug:
    var: output.stdout

, or even better

- debug:
    var: output.stdout_lines

Answer 2

While Vladimir is correct about dumping out stdout of commands with debug, kernel release and hostname can be accessed with a minimal amount of fact collection:

---
- hosts: all
  gather_facts: True
  gather_subset: min
  become: False

  tasks:
  - name: hostname
    debug:
      var: ansible_hostname

  - name: kernel version
    debug: 
      var: ansible_kernel

• Your variables are available without registering anything. You also get some bonus facts like ansible_distribution
• The min facts set is sufficient, which skips a lot of hardware detection and is fairly fast.
• Becoming a privileged user was not necessary.
• Avoided a use of shell. Which has less obvious failure modes than fact collection.