Step One: check to see if your article was published in a predatory journal via Cabell's. If it was, Google Scholar will be the only database that will index it. There are no further steps for Scopus or Web of Science.
If your article is missing from your Google Scholar profile: consult Google Scholar's Inclusion Guidelines for Webmasters. Since Google Scholar crawls through the web like Google proper does, it should capture the information for your article if the IT department for the publisher has set up their site correctly. You will have to notify the webmaster who manages that publication's database to resolve the issue.
If your article is missing from your Scopus profile: you are going to need to use Elsevier's Author Feedback Wizard to resolve the issue. Access Scopus and search for yourself by author name or ORCID. Select if you are the author or making a request on the behalf of the author and click continue. Select the option for documents and then Search for missing documents on Scopus. Select the relevant documents to add, select add document, review changes and then submit request. Remember: if the article isn't indexed in Scopus, it can't be added to an author's profile. More information on making corrections is available in How do I Request to Add a Missing Document?
If your article is missing from your Web of Science profile: log into Web of Science, access your profile and click on +ADD next to Publications. You can then add your article via DOI by selecting Add Publications by Identifier. More information on making corrections is available in Adding and Removing Publications from Web of Science Researcher Profiles.
Besides H-Index, several other author-level metrics are used to assess the impact and productivity of researchers. Here are some commonly used alternative author metrics: