How to increase the list view threshold for a list ?

The default value of any Sharepoint List is set to '5000' . If the number of items in a list exceeds this limit you might receive a threshold view error. To change this limitation you would need to change it at the web application level. 

1. Go to Central Administration 
2. Manage Web applications 
3. Click on the Web application you would want to make this change. 
4. In the ribbon above, click General Settings  and in the drop down click on 'Resource throttling'
5. Change the list view threshold in the page. 

Note: Please make sure to follow the best practices mentioned in this Microsoft blog post below when changing this number. 

https://support.microsoft.com/en-us/office/manage-large-lists-and-libraries-b8588dae-9387-48c2-9248-c24122f07c59