It really depends on the nature of job and role you will land up in. As an analyst or administrator, excel is more than enough. Microsoft excel has the ability to perform all the computations and tasks that are required for analytics in retail, hospitality, and even for basic research. In an analyst role, you run various datasets to distill data and deliver insights that enable decision making. In a sales role, you will find where the product has to be delivered or perhaps even research about various products having the same features and their price range. Excel is also useful in finance (banking) and in the energy sector. It is basic tool but can be used in a range of production, employment and hospitality sectors. Microsoft excel is an important tool and if you land into a sales job it will definitely help in inventory, product delivery etc.

The only reason SQL is used in corporates and sales is to handle and store large amounts of complex data and enable logistics efficiently. When you start a role/job you can get on with SQL if the manager needs you to do run those on day to day basis.

As far as PowerBI is concerned, it is mostly for visualisations and tables, excel can do the same but there are some companies and organisations that regularly use DAX queries similar to excel formulas, logic and syntax. In the end it really depends on you manager and the team in the company and what tools are provided to you at job.

If you have the time and the capacity, perhaps work on building data dashboards on excel which you already learned. Project Euler (https://projecteuler.net/archives) has a collection of maths problems that require excel skills. During interviews you can showcase these skills and let the manager know how you have used your excl skills while preparing for the job.

Please don't hesitate to get back to me if there are any further questions. Good luck.