Does Isaiah 45:11 Mean That We Can Command God to Heal Us?

No.

There is no need to command God to do something that He already did!

He already provided healing for you by Jesus’ stripes (1 Peter 2:24).  He doesn’t need to be commanded to do anything else about your healing.  You are the one who needs to receive the healing He provided.

Suppose that God deposits a million dollars into your bank account and sends you written confirmation that He has done so.  Then you command God to deposit a million dollars into your bank account.  God doesn’t need to make a deposit that He already made – you need to make a withdrawal!

Here is the verse in question:

Isaiah 45:11:
Thus saith the LORD, the Holy One of Israel, and his Maker, Ask me of things to come concerning my sons, and concerning the work of my hands command ye me.

We should note in passing that this does not make you “over” God or give you the right to boss God around and tell Him to do whatever you feel like having Him do.  Also, this is an Old Testament Scripture!  In the New Testament, God has already done something to meet every need you’ll ever have, so I can’t think of any case where you would NEED to command Him to do anything new for you anyway!