First you shuld know about yourself. It is so easy by using SWOT analysis. Make your mind clear that you are strong on what you know.

Second, Know your KRAs and KPIs. Sketch your profile to meet the same.

Match KRAs with SWOT analysis.

You will find where you are lagging.

Concnetrate on the mismatching points and make yuorself to overcome this.

It seems your boss is an articualte not an orator. So, you should be very careful in your vocabulary. Try to understand his language style, mannerism and influence.

Change your attitude with others as supprotive. Get confident of your colleagues that you are suitable for the psoition. This will diminish your boss's theory on you.

Moreover, he should not realise that you are oversmarting

All the best

SMS