Defending and countering the right kick, right cross, and left hook, as a southpaw (how would a southpaw defend and counter these strikes?)

I occasionally have the lead hand slightly extended to smother and prevent the jab.

I am very slow with my takedowns. My problem is Also when I pin the opponent my mind goes blank and I end up just pinning . I need to get out of my defensive way of thinking . I can defend and protect adequately but ask me to attack or finish someone and I am stumped which usually leads to me getting beatingS

Bruce Lee once said, “In a real life situation he would not kick someone in the face, just like he would not punch someone in the foot” I know it depends on the situation but what are your thoughts? I know some on here probably dont think Bruce was legit but you can talk about me, you can make fun of my family, but leave Bruce alone.. lol. So let’s everyone poke fun at my wife and kids while praising Bruce 🙂

P.S. I seem to have a problem shadow boxing. When i hit things like the bag or mitts i can flow normal but once I start shadow boxing I get stiff and feel off. What can i do to fix this and Does anyone else have this issue? I have a feeling doing the mp3 workout will help tons. Thoughts?