Bhagawadgita 1.10 & 1.11:

aparyāptaṁ tadasmākaṁ balaṁ bhīṣhmābhirakṣhitam
paryāptaṁ tvidameteṣhāṁ balaṁ bhīmābhirakṣhitam

ayaneṣhu cha sarveṣhu yathā-bhāgamavasthitāḥ
bhīṣhmamevābhirakṣhantu bhavantaḥ sarva eva hi

Here, Dhuryodhana says that his side of army is secured by unlimited power of Bheeshma who has the boon of dying only at his will. So he considers this as the strength of his side while comparing Bheeshma with Pandavas side Bheem.  Bheem definitely has limited power, but Dhuryodhan wrongly compares Bheeshma with Bheem. Bheeshma has to be compared with Lord Krishna who is there on the Pandava’s. Krishna’s mere presence means that Dharma or the righteousness is on the Pandavas side which means, only Pandavas will win the war. But Dhuryodhan, being in the illusion that Krishna does not fight in the war, so he forgets the importance of lord Krishna and his presence. Hence, he wrongly intangibly compares Bheesma with Bheem, to encourage his generals.

Dhuryodhan is also concerned that Bheeshma has soft corner for Pandavas and thus if the situation comes, he might give up his own life instead of fighting with Pandavas.

So he asks all his generals to take care of the invincible Bheeshma while taking care of their own positions.

 Bhagawadgita 1.12 and 1.13:

Asya sanjanayan harsham kuru-vriddhah pitamahah
simha-nadam vinadyochchaih shankham dadhmau pratapavan

atah shankhashcha bheryashcha panavanaka-gomukhah
sahasaivabhyahanyanta sa shabdastumulo ’bhavat

Then, Bheeshma, blows the conch shell which is the sign of showing the readiness of fighting the war. Following Bheeshma, some of the army men, made various sounds of trumpets and other instruments which created mayhem of noise and uproar.

Bhagawadgita 1.14:

tataḥ śhvetairhayairyukte mahati syandane sthitau
mādhavaḥ pāṇḍavaśhchaiva divyau śhaṅkhau pradadhmatuḥ

As the Kauravas made the war sounds, Lord Shree Krishna and Arjuna blew their conch shells.

Shree Krishna is addressed as Madhava which means, Lord Krishna is the husband of Ma, referring to Goddess Lakshmi who supports the dharma, prosperity and victory.

Bhagawadgita 1.15 to 1.18:

pāñchajanyaṁ hṛiṣhīkeśho devadattaṁ dhanañjayaḥ
pauṇḍraṁ dadhmau mahā-śhaṅkhaṁ bhīma-karmā vṛikodaraḥ

anantavijayaṁ rājā kuntī-putro yudhiṣhṭhiraḥ
nakulaḥ sahadevaśhcha sughoṣha-maṇipuṣhpakau

kāśhyaśhcha parameṣhvāsaḥ śhikhaṇḍī cha mahā-rathaḥ
dhṛiṣhṭadyumno virāṭaśhcha sātyakiśh chāparājitaḥ
drupado draupadeyāśhcha sarvaśhaḥ pṛithivī-pate
saubhadraśhcha mahā-bāhuḥ śhaṅkhāndadhmuḥ pṛithak pṛithak

Lord Shree Krishna is mentioned as Hrishikesh which means, he is the one who controls the minds and senses. Lord Krishna, Arjuna and Bheem blew their own instruments showing their readiness for the war.

Rest all other Pandava brothers and rest other important personalities also showed their readiness by making the sounds of their own instruments.

Bhagawadgita 1.19:

sa ghoṣho dhārtarāṣhṭrāṇāṁ hṛidayāni vyadārayat
nabhaśhcha pṛithivīṁ chaiva tumulo abhyanunādayan

Sanjaya narrates Dhritarastra that the thundered sounds of Pandavas side have shattered the hearts of Kauravas which means, the weeping conscience of kauravas inside are aware of the sins and crimes they committed though they swallow all such soul cry inside and fight with only physical strength which is mere in front of strength of the spirit.

Bhagawadgita 1.20:

atha vyavasthitān dṛiṣhṭvā dhārtarāṣhṭrān kapi-dhwajaḥ
pravṛitte śhastra-sampāte dhanurudyamya pāṇḍavaḥ
hṛiṣhīkeśhaṁ tadā vākyam idam āha mahī-pate

Arjuna has Lord Hanuman’s flag on his chariot which is the sign of victory. Lord Hanuman also worked spiritually, supporting Arjuna.

 Bhagawadgita 1.21 & 22:

arjuna uvācha
senayor ubhayor madhye rathaṁ sthāpaya me ’chyuta
yāvadetān nirīkṣhe ’haṁ yoddhu-kāmān avasthitān
kairmayā saha yoddhavyam asmin raṇa-samudyame

Arjuna asks Lord Shree Krishna to take the chariot to the middle of the armies so that he could see the enemy side army men with whom he has to fight.

Bhagawadgita 1.23 & 24:

yotsyamānān avekṣhe ’haṁ ya ete ’tra samāgatāḥ
dhārtarāṣhṭrasya durbuddher yuddhe priya-chikīrṣhavaḥ

sañjaya uvācha
evam ukto hṛiṣhīkeśho guḍākeśhena bhārata
senayor ubhayor madhye sthāpayitvā rathottamam

Arjuna says to lord Shree Krishna that he wants to see the men who came to please and support the evil minded Dhuryodhana.  Then, Shree Krishna takes the chariot to the middle of the two armies.