Philippians 4:13 is a text often quoted out of context to support the idea that the quoter can do anything that they set their mind to if it is according to God's will and they rely on God's strength.
So far as I can see, there are three problems with this:
1. We can't be sure what God's will is in every situation.
2. God's will doesn't always take place in this sinful world.
3. This verse is taken out of context and made to mean something different from the original meaning.
Let us look at this verse in context.
But I rejoiced in the Lord greatly, that now at the last your care of me hath flourished again; wherein ye were also careful, but ye lacked opportunity. Not that I speak in respect of want: for I have learned, in whatsoever state I am, therewith to be content. I know both how to be abased, and I know how to abound: every where and in all things I am instructed both to be full and to be hungry, both to abound and to suffer need. I can do all things through Christ which strengtheneth me. - Philippians 4:10-13 (KJV)
Paul has learned the secret of radical acceptance. I can radically accept every situation that I am in through Christ who strengthens me. Radical acceptance does not mean leaving things as they are. Radical acceptance involves accepting reality as it is and then working to change what can be changed. This is what Paul was able to do through the strength of Christ.
God has given each individual a certain personality with unique gifts and talents and intelligence to choose a work that is suited to them. God doesn't want everyone to be nurses, teachers, doctors, pastors, literature evangelists and bible workers. God created some people who are better suited to working behind the scenes rather than upfront. Those people should be valued for their contribution and not pressured to "claim Philippians 4:13" and work on the front lines. God needs cleaners, cooks, accountants, etc. just as much as other workers. Don't be ashamed to work behind the scenes. Your work is just as important.
I would like to conclude this piece by quoting Philippians 4:10-13 from the Good News Translation.
In my life in union with the Lord it is a great joy to me that after so long a time you once more had the chance of showing that you care for me. I don't mean that you had stopped caring for me—you just had no chance to show it. And I am not saying this because I feel neglected, for I have learned to be satisfied with what I have. I know what it is to be in need and what it is to have more than enough. I have learned this secret, so that anywhere, at any time, I am content, whether I am full or hungry, whether I have too much or too little. I have the strength to face all conditions by the power that Christ gives me. - Philippians 4:10-13 (GNT)