How to get thicker hair???

So as a baby my parents shaved my head. Couple times! I grew up with horse hair and it’s so thick!! Recently I went through a hard week of being depressed,in a slump with 0 motivation for anything.During that week I didn’t brush my hair at all,I had a literal messy bun all week.When I decided to de tangle my rats nest,I got in the shower covered my head in conditioner! And used my finger and a wet brush to slowly de tangle,my hair was falling out in clumps (due to the breakage I caused).To me I see a difference in my hair now,it’s for sure thinner😢Does anyone have any tips of getting my hair thicker?? Or some good hair products to use?? What I’ve taken away from this mental breakdown now about my hair🤦🏽‍♀️ is 2 always keep it brushed out and maintained regardless😤😤