I solved by simply replacing the highlighted line in the image with the path of the security certificate I had generated for elasticsearch.
i remove --fleet-server-es-ca-trusted-fingerprint
and add --fleet-server-es-ca with de path of de certificate for elasticsearch
curl -L -O https://artifacts.elastic.co/downloads/beats/elastic-agent/elastic-agent-8.14.3-linux-x86_64.tar.gz
tar xzvf elastic-agent-8.14.3-linux-x86_64.tar.gz
cd elastic-agent-8.14.3-linux-x86_64
sudo ./elastic-agent install \
--fleet-server-es=https://172.26.6.6:9200 \
--fleet-server-service-token=AAEAAWVsYXN0aWMvZmxlZXQtc2VydmVyL3Rva2VuLTE3MjQ4NTQxNzAwODk6cVlvWkEtQzhRb3FGRDhnVlgwc3Z3Zw \
--fleet-server-policy=fleet-server-policy \
--fleet-server-es-ca=/etc/elasticsearch/certs/certificado-ca.crt \
--fleet-server-port=8220
