A deceptive, almost surrealistic atmosphere of tranquility settled over the Israeli side of the Syrian border today in sharp contrast to the bellicose rhetoric that accompanied Israel's annexation of the strategic plateau overlooking the Galilee Valley.

As Israeli Defense Minister Ariel Sharon toured military installations in the heights and Army Chief of Staff Maj. Gen. Rafael Eitan cut short an official visit to Egypt to rush home amid reports of a heavy Syrian buildup, this fowardmost Israeli Army bunker barely 200 yards from the Syrian frontier looked no different to a visitor today than it did during another visit two weeks ago, before any hint of Prime Minister Menachem Begin's annexation decision.

Indeed, all along the border, from Kuneitra in the north to the junction of the Israeli, Syrian and Jordanian frontiers south of the Sea of Galilee, there was no visible evidence of military activity or deployment of troops or equipment on either side.

Under a blue, cloudless sky in unseasonable springlike weather, Syrian farmers could be seen tending their lush, green crops just outside Kuneitra, the ghost town that was heavily damaged by the Israeli Army before it was returned to Syria under the 1974 disengagement agreement.

Infrequently, a solitary white U.N. peace-keeping force jeep could be seen meandering along the nearly deserted and potholed roads that run alongside the frontier, but the restricted approaches to this Israeli hilltop bunker seemed so far removed from a war preparedness footing that two foreign journalists traveling in a civilian automobile with foreign license plates went unnoticed until they came to within a few yards of the no man's land between the two enemy lines.

Nearby, a U.N. disengagement observer force civilian technician basked in the sun as he waited for a military escort to a U.N. observation post. He said that despite reports on Israeli Army radio of an alert and deployment of troops last night, the frontier had been as uneventful as it normally is.

"Nothing has changed. It's absolutely normal, and let's hope it stays that way," the Irish U.N. employe said.

But in Jerusalem, there were still reverberations from the series of lightning-fast parliamentary moves that Begin forced through the Knesset to win a decisive 63 to 21 victory for his bill to "apply Israeli law" to the 500-square-mile Golan Heights, which was occupied by Israel during the 1967 Six-Day War.

As he toured military bases here by helicopter, Sharon was quoted by the Army radio as saying that the Israeli Defense Forces were taking all the necessary steps to prepare for a buildup of Syrian forces along the border. Also, Sharon said, the Army was prepared to counter infiltration by terrorist squads, and had considered the possibility of a renewed cross-border war of attrition. The defense minister, however, did not specify what steps the Army had taken.

Despite a stiff rebuke from the Egyptian government calling the annexation vote "illegitimate," an Egyptian-Israeli technical committee resumed negotiations in Tel Aviv this morning on the proposed autonomy for the West Bank and Gaza Strip Palestinians, and Egypt said that the Knesset action would not interrupt the Camp David peace process.

There was a festive atmosphere in the town of Katzrin today, one of 31 settlements housing 6,500 Jewish settlers in the Golan Heights. Residents had celebrated and danced in the streets late into the night.

Shimon Sheves, chairman of the Golan Settlements Committee, enthusiastically predicted that the Knesset vote will result in an influx of thousands of new settlers to the Golan because the fear of the territory ever being returned to Syria has been removed.

"It's a very important decision. It makes the Golan part of Israel. We suppose the government will build many buildings in the Golan . . . .It will be a strong border. It is the decision of Israel that Israel will stay in the Golan forever," Sheves said.

Reaction among the 12,500 Golan Heights members of the Druze sect, a splinter of Islam, appeared to be divided sharply, with those who since 1967 have been pro-Syrian expressing anger and disappointment, and those who have been pro-Israel rejoicing at the decision. The Druzes, along with about 800 Alawite Moslems, remained or are descended from those who remained in the Golan Heights after the 1967 war.

Salman Abu Salah, a Druze of the Mt. Hermon town of Magdal Shams and head of the Druze-Israel Friendship League, predicted in a Radio Israel interview that many Golan Heights Arabs would overcome their fear of annexation and apply for Israeli citizenship.

Last year, during an Israeli campaign to sign up Druze residents for citizenship, about 1,500 accepted Israeli identity cards, but later, under intense pressure from local religious leaders, all but 30 of them returned the cards to the authorities. Salah retained his citizenship.

Meanwhile, Sheik Suleiman Kange, head of the pro-Syrian Druze movement in Magdal Shams, said yesterday was the "blackest day" of his life, and vowed to never give up his Syrian citizenship.

His cousin, Kamal Kange, was quoted by Israel Radio as saying, "there is no difference in the feeling of the people . . . .They feel they are Arabic and of true Arabic blood, and so they feel for their dignity, their honor and all their values."